It's currently trying to load with the name as the key, which should never be the case.

invokeai/app/invocations/compel.py

@@ -86,7 +86,9 @@ class CompelInvocation(BaseInvocation):
         for trigger in extract_ti_triggers_from_prompt(self.prompt):
             name = trigger[1:-1]
             try:
-                loaded_model = context.models.load(key=name).model
+                loaded_model = context.models.load_by_attrs(
+                    model_name=name, base_model=text_encoder_info.config.base, model_type=ModelType.TextualInversion
+                ).model
                 assert isinstance(loaded_model, TextualInversionModelRaw)
                 ti_list.append((name, loaded_model))
             except UnknownModelException:

invokeai/app/util/ti_utils.py

@@ -1,8 +1,10 @@
 import re
 
+from typing import List
 
-def extract_ti_triggers_from_prompt(prompt: str) -> list[str]:
-    ti_triggers = []
+
+def extract_ti_triggers_from_prompt(prompt: str) -> List[str]:
+    ti_triggers: List[str] = []
     for trigger in re.findall(r"<[a-zA-Z0-9., _-]+>", prompt):
-        ti_triggers.append(trigger)
+        ti_triggers.append(str(trigger))
     return ti_triggers