diff --git a/litellm/llms/vertex_ai/vertex_ai_non_gemini.py b/litellm/llms/vertex_ai/vertex_ai_non_gemini.py
index 418d8813dc1a..744e1eb3177d 100644
--- a/litellm/llms/vertex_ai/vertex_ai_non_gemini.py
+++ b/litellm/llms/vertex_ai/vertex_ai_non_gemini.py
@@ -7,6 +7,7 @@
 
 import litellm
 from litellm.litellm_core_utils.core_helpers import map_finish_reason
+from litellm.llms.bedrock.common_utils import ModelResponseIterator
 from litellm.llms.custom_httpx.http_handler import _DEFAULT_TTL_FOR_HTTPX_CLIENTS
 from litellm.types.llms.vertex_ai import *
 from litellm.utils import CustomStreamWrapper, ModelResponse, Usage
@@ -197,6 +198,7 @@ def completion(  # noqa: PLR0915
         client_options = {
             "api_endpoint": f"{vertex_location}-aiplatform.googleapis.com"
         }
+        fake_stream = False
         if (
             model in litellm.vertex_language_models
             or model in litellm.vertex_vision_models
@@ -220,6 +222,7 @@ def completion(  # noqa: PLR0915
             )
             mode = "text"
             request_str += f"llm_model = CodeGenerationModel.from_pretrained({model})\n"
+            fake_stream = True
         elif model in litellm.vertex_code_chat_models:  # vertex_code_llm_models
             llm_model = _vertex_llm_model_object or CodeChatModel.from_pretrained(model)
             mode = "chat"
@@ -275,17 +278,22 @@ def completion(  # noqa: PLR0915
             return async_completion(**data)
 
         completion_response = None
+
+        stream = optional_params.pop(
+            "stream", None
+        )  # See note above on handling streaming for vertex ai
         if mode == "chat":
             chat = llm_model.start_chat()
             request_str += "chat = llm_model.start_chat()\n"
 
-            if "stream" in optional_params and optional_params["stream"] is True:
+            if fake_stream is not True and stream is True:
                 # NOTE: VertexAI does not accept stream=True as a param and raises an error,
                 # we handle this by removing 'stream' from optional params and sending the request
                 # after we get the response we add optional_params["stream"] = True, since main.py needs to know it's a streaming response to then transform it for the OpenAI format
                 optional_params.pop(
                     "stream", None
                 )  # vertex ai raises an error when passing stream in optional params
+
                 request_str += (
                     f"chat.send_message_streaming({prompt}, **{optional_params})\n"
                 )
@@ -298,6 +306,7 @@ def completion(  # noqa: PLR0915
                         "request_str": request_str,
                     },
                 )
+
                 model_response = chat.send_message_streaming(prompt, **optional_params)
 
                 return model_response
@@ -314,10 +323,8 @@ def completion(  # noqa: PLR0915
             )
             completion_response = chat.send_message(prompt, **optional_params).text
         elif mode == "text":
-            if "stream" in optional_params and optional_params["stream"] is True:
-                optional_params.pop(
-                    "stream", None
-                )  # See note above on handling streaming for vertex ai
+
+            if fake_stream is not True and stream is True:
                 request_str += (
                     f"llm_model.predict_streaming({prompt}, **{optional_params})\n"
                 )
@@ -384,7 +391,7 @@ def completion(  # noqa: PLR0915
                 and "\nOutput:\n" in completion_response
             ):
                 completion_response = completion_response.split("\nOutput:\n", 1)[1]
-            if "stream" in optional_params and optional_params["stream"] is True:
+            if stream is True:
                 response = TextStreamer(completion_response)
                 return response
         elif mode == "private":
@@ -413,7 +420,7 @@ def completion(  # noqa: PLR0915
                 and "\nOutput:\n" in completion_response
             ):
                 completion_response = completion_response.split("\nOutput:\n", 1)[1]
-            if "stream" in optional_params and optional_params["stream"] is True:
+            if stream is True:
                 response = TextStreamer(completion_response)
                 return response
 
@@ -465,6 +472,9 @@ def completion(  # noqa: PLR0915
                 total_tokens=prompt_tokens + completion_tokens,
             )
         setattr(model_response, "usage", usage)
+
+        if fake_stream is True and stream is True:
+            return ModelResponseIterator(model_response)
         return model_response
     except Exception as e:
         if isinstance(e, VertexAIError):
diff --git a/litellm/utils.py b/litellm/utils.py
index f3789fe12940..2ab06ba89ad4 100644
--- a/litellm/utils.py
+++ b/litellm/utils.py
@@ -4224,6 +4224,7 @@ def _get_model_info_helper(  # noqa: PLR0915
             _model_info: Optional[Dict[str, Any]] = None
             key: Optional[str] = None
             provider_config: Optional[BaseLLMModelInfo] = None
+
             if combined_model_name in litellm.model_cost:
                 key = combined_model_name
                 _model_info = _get_model_info_from_model_cost(key=key)
@@ -4263,7 +4264,10 @@ def _get_model_info_helper(  # noqa: PLR0915
                 ):
                     _model_info = None
 
-            if custom_llm_provider:
+            if custom_llm_provider and custom_llm_provider in [
+                provider.value for provider in LlmProviders
+            ]:
+                # Check if the provider string exists in LlmProviders enum
                 provider_config = ProviderConfigManager.get_provider_model_info(
                     model=model, provider=LlmProviders(custom_llm_provider)
                 )
diff --git a/tests/local_testing/test_amazing_vertex_completion.py b/tests/local_testing/test_amazing_vertex_completion.py
index 0dc814961101..e7bca6bc13f5 100644
--- a/tests/local_testing/test_amazing_vertex_completion.py
+++ b/tests/local_testing/test_amazing_vertex_completion.py
@@ -930,7 +930,7 @@ async def test_gemini_pro_function_calling_httpx(model, sync_mode):
         "vertex_ai/mistral-large@2407",
         "vertex_ai/mistral-nemo@2407",
         "vertex_ai/codestral@2405",
-        "vertex_ai/meta/llama3-405b-instruct-maas",
+        # "vertex_ai/meta/llama3-405b-instruct-maas",
     ],  #
 )  # "vertex_ai",
 @pytest.mark.parametrize(
@@ -960,7 +960,6 @@ async def test_partner_models_httpx(model, sync_mode):
             "model": model,
             "messages": messages,
             "timeout": 10,
-            "mock_response": "Hello, how are you?",
         }
         if sync_mode:
             response = litellm.completion(**data)
@@ -993,7 +992,8 @@ async def test_partner_models_httpx(model, sync_mode):
     "model",
     [
         "vertex_ai/mistral-large@2407",
-        "vertex_ai/meta/llama3-405b-instruct-maas",
+        # "vertex_ai/meta/llama3-405b-instruct-maas",
+        "vertex_ai/codestral@2405",
     ],  #
 )  # "vertex_ai",
 @pytest.mark.parametrize(
@@ -1023,7 +1023,6 @@ async def test_partner_models_httpx_streaming(model, sync_mode):
             "model": model,
             "messages": messages,
             "stream": True,
-            "mock_response": "Hello, how are you?",
         }
         if sync_mode:
             response = litellm.completion(**data)
@@ -3193,3 +3192,16 @@ async def test_vertexai_model_garden_model_completion(
     assert response.usage.completion_tokens == 109
     assert response.usage.prompt_tokens == 63
     assert response.usage.total_tokens == 172
+
+
+def test_vertexai_code_gecko():
+    litellm.set_verbose = True
+    load_vertex_ai_credentials()
+    response = completion(
+        model="vertex_ai/code-gecko@002",
+        messages=[{"role": "user", "content": "Hello world!"}],
+        stream=True,
+    )
+
+    for chunk in response:
+        print(chunk)
diff --git a/tests/local_testing/test_get_model_info.py b/tests/local_testing/test_get_model_info.py
index 29c02c7cc5ad..2c313cecad1f 100644
--- a/tests/local_testing/test_get_model_info.py
+++ b/tests/local_testing/test_get_model_info.py
@@ -247,3 +247,41 @@ def test_model_info_bedrock_converse_enforcement(monkeypatch):
             )
     except FileNotFoundError as e:
         pytest.skip("whitelisted_bedrock_models.txt not found")
+
+
+def test_get_model_info_custom_provider():
+    # Custom provider example copied from https://docs.litellm.ai/docs/providers/custom_llm_server:
+    import litellm
+    from litellm import CustomLLM, completion, get_llm_provider
+
+    class MyCustomLLM(CustomLLM):
+        def completion(self, *args, **kwargs) -> litellm.ModelResponse:
+            return litellm.completion(
+                model="gpt-3.5-turbo",
+                messages=[{"role": "user", "content": "Hello world"}],
+                mock_response="Hi!",
+            )  # type: ignore
+
+    my_custom_llm = MyCustomLLM()
+
+    litellm.custom_provider_map = [  # 👈 KEY STEP - REGISTER HANDLER
+        {"provider": "my-custom-llm", "custom_handler": my_custom_llm}
+    ]
+
+    resp = completion(
+        model="my-custom-llm/my-fake-model",
+        messages=[{"role": "user", "content": "Hello world!"}],
+    )
+
+    assert resp.choices[0].message.content == "Hi!"
+
+    # Register model info
+    model_info = {"my-custom-llm/my-fake-model": {"max_tokens": 2048}}
+    litellm.register_model(model_info)
+
+    # Get registered model info
+    from litellm import get_model_info
+
+    get_model_info(
+        model="my-custom-llm/my-fake-model"
+    )  # 💥 "Exception: This model isn't mapped yet." in v1.56.10