I've finished every section of the quest but when I go to turn it into Karolak Nightspinner he is hostile and I have to fight the boss again, after finishing the boss there is still no quest giver to finish the quest. Please help :(
Sorry to hear you're having troubles! If you're caught in a state where you can't advance your quest, please contact our Customer Support for more assistance.
I'm not sure whether or not you have done this yet but make sure to go in alone and he is there as a npc, it is only until after you talk to him there when he turns hostile.