Your information is severely outdated. Morek has not been pure SA in, like, forever. Some duchies dont even require you to be a member to be a lord. Some of their council members used to be pagans. If there were another religion on Dwilight, it would certainly be allowed in Morek, so long as it wasnt adversarial toward SA.
Really, your post is all fear mongering and sensationalism. You're describing a situation that stopped being true years ago.