I didn't like the faction so I killed everyone including the future NPC questgiver. Once I progressed the main story, the quest marker would point to a floating point where their head would be, and you could hear the dialogue of the all the dead NPC ghosts taking to eachother.
5 years later and still not fixed so I still haven't beaten the game or played the DLC's. Didn't feel like starting from the beginning and risking the bug again.