Knights of Truth guards don't have the right faction hits.
 

https://everquest.allakhazam.com/db/npc.html?id=983

Should be

+15 Dismal Rage
+15 Freeport Militia
-20 Priests of Marr
-10 Steel Warriors
-100 Knights of Truth

I can't speak to Priests of Marr or Steel Warriors, but I stayed dubious despite 20 kills on both the Militia and Dismal Rage.

Dubious has a 250 faction spread and I should have gotten 300+ Faction with both, putting me at Apprehensive.