diff --git a/litellm/proxy/guardrails/guardrail_hooks/grayswan/grayswan.py b/litellm/proxy/guardrails/guardrail_hooks/grayswan/grayswan.py
index 8955bffc125..b8a1566160e 100644
--- a/litellm/proxy/guardrails/guardrail_hooks/grayswan/grayswan.py
+++ b/litellm/proxy/guardrails/guardrail_hooks/grayswan/grayswan.py
@@ -545,7 +545,9 @@ class GraySwanGuardrail(CustomGuardrail):
         if "metadata" in dynamic_body:
             payload["metadata"] = dynamic_body["metadata"]
 
-        litellm_metadata = request_data.get("litellm_metadata")
+        litellm_metadata = request_data.get("litellm_metadata") or request_data.get(
+            "_guardrail_litellm_metadata"
+        )
         if isinstance(litellm_metadata, dict) and litellm_metadata:
             cleaned_litellm_metadata = dict(litellm_metadata)
             # cleaned_litellm_metadata.pop("user_api_key_auth", None)
diff --git a/litellm/proxy/guardrails/guardrail_hooks/unified_guardrail/unified_guardrail.py b/litellm/proxy/guardrails/guardrail_hooks/unified_guardrail/unified_guardrail.py
index 367e6b2f150..e861a67278b 100644
--- a/litellm/proxy/guardrails/guardrail_hooks/unified_guardrail/unified_guardrail.py
+++ b/litellm/proxy/guardrails/guardrail_hooks/unified_guardrail/unified_guardrail.py
@@ -53,8 +53,13 @@ endpoint_guardrail_translation_mappings = None
 
 
 def _ensure_litellm_metadata(data: dict, user_api_key_dict: UserAPIKeyAuth) -> None:
-    """Populate data['litellm_metadata'] from user_api_key_dict if absent."""
-    if "litellm_metadata" not in data:
+    """Populate data['litellm_metadata'] from user_api_key_dict if absent.
+
+    Uses '_guardrail_litellm_metadata' as the key when 'litellm_metadata' is not
+    already present, to avoid interfering with get_metadata_variable_name_from_kwargs()
+    which switches metadata routing when 'litellm_metadata' exists.
+    """
+    if "litellm_metadata" not in data and "_guardrail_litellm_metadata" not in data:
         from litellm.llms.base_llm.guardrail_translation.base_translation import (
             BaseTranslation,
         )
@@ -63,7 +68,7 @@ def _ensure_litellm_metadata(data: dict, user_api_key_dict: UserAPIKeyAuth) -> N
             user_api_key_dict
         )
         if user_metadata:
-            data["litellm_metadata"] = user_metadata
+            data["_guardrail_litellm_metadata"] = user_metadata
 
 
 class UnifiedLLMGuardrails(CustomLogger):
diff --git a/tests/test_litellm/proxy/guardrails/guardrail_hooks/test_grayswan.py b/tests/test_litellm/proxy/guardrails/guardrail_hooks/test_grayswan.py
index 14cf732aa7c..d5f9d66870d 100644
--- a/tests/test_litellm/proxy/guardrails/guardrail_hooks/test_grayswan.py
+++ b/tests/test_litellm/proxy/guardrails/guardrail_hooks/test_grayswan.py
@@ -477,8 +477,28 @@ def test_prepare_payload_includes_litellm_metadata(
     assert payload["litellm_metadata"]["user_api_key_team_id"] == "team-456"
 
 
+def test_prepare_payload_includes_guardrail_litellm_metadata(
+    grayswan_guardrail: GraySwanGuardrail,
+) -> None:
+    """Verify _prepare_payload reads from _guardrail_litellm_metadata fallback."""
+    messages = [{"role": "user", "content": "hello"}]
+    request_data = {
+        "_guardrail_litellm_metadata": {
+            "user_api_key_user_id": "user-pre",
+            "user_api_key_team_id": "team-pre",
+        }
+    }
+
+    payload = grayswan_guardrail._prepare_payload(messages, {}, request_data)
+
+    assert payload is not None
+    assert "litellm_metadata" in payload
+    assert payload["litellm_metadata"]["user_api_key_user_id"] == "user-pre"
+    assert payload["litellm_metadata"]["user_api_key_team_id"] == "team-pre"
+
+
 def test_ensure_litellm_metadata_populates_from_user_api_key_dict() -> None:
-    """Verify _ensure_litellm_metadata populates from user_api_key_dict."""
+    """Verify _ensure_litellm_metadata populates _guardrail_litellm_metadata."""
     from litellm.proxy.guardrails.guardrail_hooks.unified_guardrail.unified_guardrail import (
         _ensure_litellm_metadata,
     )
@@ -488,9 +508,11 @@ def test_ensure_litellm_metadata_populates_from_user_api_key_dict() -> None:
 
     _ensure_litellm_metadata(data, user_auth)
 
-    assert "litellm_metadata" in data
-    assert data["litellm_metadata"]["user_api_key_user_id"] == "u1"
-    assert data["litellm_metadata"]["user_api_key_team_id"] == "t1"
+    # Uses _guardrail_ prefix to avoid interfering with metadata routing
+    assert "_guardrail_litellm_metadata" in data
+    assert "litellm_metadata" not in data
+    assert data["_guardrail_litellm_metadata"]["user_api_key_user_id"] == "u1"
+    assert data["_guardrail_litellm_metadata"]["user_api_key_team_id"] == "t1"
 
 
 def test_ensure_litellm_metadata_noop_when_already_present() -> None:
@@ -505,3 +527,4 @@ def test_ensure_litellm_metadata_noop_when_already_present() -> None:
     _ensure_litellm_metadata(data, user_auth)
 
     assert data["litellm_metadata"] == {"existing": "value"}
+    assert "_guardrail_litellm_metadata" not in data