I know that you can't find Tarkus down in the cells, but reading on the forums a person said that if you reach Redbeard at the bottom, you could return to the hand who gave you the quest and turn it in. I can't. I've thoroughly searched everything down there and she just says the same stuff when I go to her to turn the quest in. Was the person wrong when they said that you can turn it in after talking to Redbeard down there, or have I encountered a bug which prevents me from completing this quest?