If you get to this quest, and do not turn in immediately the marker for the turn in tends to vanish. The quest itself is not bugged, just the marker (due to a spawn and run up to you npc who is the marker locale, it does not show unless you are in a given area.) To turn it is go to the triangular area south west of the main graveyard. You should get the npc to spawn and run up to you once you do.
http://puu.sh/80rKN.jpg should show the location, thanks to a nice person who posted it on the ESO forums.
