Not sure if this is the same as an earlier now deleted posting but...
If he is spoken to, the quest does not update and you cannot end the quest. The first time this happened, a DM helped us out (derflaro I think) BUT about an hour later, with only two other people on the server and my original party logged off, I got a random message in my log that we had killed the apprentice and I was then able to turn the quest in. FYI, we had NOT killed him.
What do you mean by spoken to. You mean you successfully managed to convince him NOT to fight? or you just spoke to him prior to attacking?
After convincing him to not attack us, the group of eight left the QA and told Muskroot (The journal only updated for me, reportedly) that the Apprentice will speak with him.
He said grand news, and gave me some mole claw gloves.
No XP reward or journal update saying "Completed quest."
Nor was there gold.
Thanks! Helps a lot.