i have this same problem with old thralls suddenly respawning hostile after a fast travel. i have done a lot of necromancy so it is a bit absurd when it happens because the entire area becomes a war zone. I have not downloaded the mod you mentioned so it has nothing to do with that i think. It would be nice if anyone had an answer for this because i like necromancy and it would suck to not be able to use it because of this bug.