Nope, the quest hasn't been completed. The quest was still listed under the "to do" tab, and I still had the un-upgraded amulet. As far as I know I didn't do anything to disable or void his quest, and I haven't come across anything that uses or talks about the mummy hand. But I've given up hope of competing the quest and moved on, I'm now in Lusken. When I entered Lusken, my journal cleared and I lost all quest items from the first part of chapter two. So I don't even have the hand any more. But because I didn't complete the quest, Grimgnaw won't continue his story... so I guess I've lost out on that for the rest of the game
Oh well. The ending of chapter two is proving to be very interesting though.
I did find the guy who makes things in chapter one. I made a lot of money off of him
I tried to do that with Gilles too, but I was never able to kill him before he left, so i just gave them to Oleff.
Thanks!