I tried to release my undead, and they were certainly removed from my party, but they kept following me around, even through transitions. I even tried relogging, and that didn't do anything, it just teleported the undead to me.
I am a sorcerer, carrion feaster, level 7.
This also happens with the conjur shadow spell. You can't seem to fully release your shadow clone.
Did little something on this, lets see how if it changes this issue.