Not sure if this has been posted, but Illians get "do you want to convert to this religion" dialogues even though they can't convert. This sometimes gets you a free relations bonus (if a leader demands you convert to their religion you can say yes, get the relations boost, but not actually convert) but otherwise it doesn't matter. I assume the Grigori have the same issue. I'm not sure is this is an issue with this modmod or Tholals. Probably the latter.