diff --git a/metadata-ingestion/src/datahub/ingestion/source/redshift/lineage_v2.py b/metadata-ingestion/src/datahub/ingestion/source/redshift/lineage_v2.py
index e7cc5fc50cf6e..4b84c25965a99 100644
--- a/metadata-ingestion/src/datahub/ingestion/source/redshift/lineage_v2.py
+++ b/metadata-ingestion/src/datahub/ingestion/source/redshift/lineage_v2.py
@@ -57,6 +57,7 @@ def __init__(
         self.context = context
 
         self.database = database
+        self.known_urns: Set[str] = set()  # will be set later
 
         self.aggregator = SqlParsingAggregator(
             platform=self.platform,
@@ -68,6 +69,7 @@ def __init__(
             generate_operations=False,
             usage_config=self.config,
             graph=self.context.graph,
+            is_temp_table=self._is_temp_table,
         )
         self.report.sql_aggregator = self.aggregator.report
 
@@ -87,7 +89,16 @@ def __init__(
             self.report.lineage_end_time,
         ) = self._lineage_v1.get_time_window()
 
-        self.known_urns: Set[str] = set()  # will be set later
+    def _is_temp_table(self, name: str) -> bool:
+        return (
+            DatasetUrn.create_from_ids(
+                self.platform,
+                name,
+                env=self.config.env,
+                platform_instance=self.config.platform_instance,
+            ).urn()
+            not in self.known_urns
+        )
 
     def build(
         self,
@@ -107,15 +118,6 @@ def build(
             for schema, tables in schemas.items()
             for table in tables
         }
-        self.aggregator._is_temp_table = (
-            lambda name: DatasetUrn.create_from_ids(
-                self.platform,
-                name,
-                env=self.config.env,
-                platform_instance=self.config.platform_instance,
-            ).urn()
-            not in self.known_urns
-        )
 
         # Handle all the temp tables up front.
         if self.config.resolve_temp_table_in_lineage:
diff --git a/metadata-ingestion/src/datahub/sql_parsing/sql_parsing_aggregator.py b/metadata-ingestion/src/datahub/sql_parsing/sql_parsing_aggregator.py
index 5c3a6b5b533a0..f0496379c45b8 100644
--- a/metadata-ingestion/src/datahub/sql_parsing/sql_parsing_aggregator.py
+++ b/metadata-ingestion/src/datahub/sql_parsing/sql_parsing_aggregator.py
@@ -537,8 +537,13 @@ def _maybe_format_query(self, query: str) -> str:
         return query
 
     @functools.lru_cache(maxsize=128)
-    def _name_from_urn(self, urn: UrnStr) -> str:
-        name = DatasetUrn.from_string(urn).name
+    def _name_from_urn(self, urn: UrnStr) -> Optional[str]:
+        urn_obj = DatasetUrn.from_string(urn)
+        if urn_obj.platform != self.platform.urn():
+            # If this is external (e.g. s3), we don't know the name.
+            return None
+
+        name = urn_obj.name
         if (
             platform_instance := self._schema_resolver.platform_instance
         ) and name.startswith(platform_instance):
@@ -549,14 +554,22 @@ def _name_from_urn(self, urn: UrnStr) -> str:
     def is_temp_table(self, urn: UrnStr) -> bool:
         if self._is_temp_table is None:
             return False
-        return self._is_temp_table(self._name_from_urn(urn))
+        name = self._name_from_urn(urn)
+        if name is None:
+            # External tables are not temp tables.
+            return False
+        return self._is_temp_table(name)
 
-    def is_allowed_table(self, urn: UrnStr) -> bool:
+    def is_allowed_table(self, urn: UrnStr, allow_external: bool = True) -> bool:
         if self.is_temp_table(urn):
             return False
         if self._is_allowed_table is None:
             return True
-        return self._is_allowed_table(self._name_from_urn(urn))
+        name = self._name_from_urn(urn)
+        if name is None:
+            # Treat external tables specially.
+            return allow_external
+        return self._is_allowed_table(name)
 
     def add(
         self,
@@ -852,7 +865,7 @@ def add_preparsed_query(
             upstream_fields = parsed.column_usage or {}
             for upstream_urn in parsed.upstreams:
                 # If the upstream table is a temp table or otherwise denied by filters, don't log usage for it.
-                if not self.is_allowed_table(upstream_urn) or (
+                if not self.is_allowed_table(upstream_urn, allow_external=False) or (
                     require_out_table_schema
                     and not self._schema_resolver.has_urn(upstream_urn)
                 ):