I finally hit lvl 80 and did the first part of the event..got exp for it after I turned in the quest. Then I went for the boss when the quest popped up. It spawned and I damaged it with a full page of damage. But when the boss died I didn't receive a reward. I have a quest for the Wraith Siege Plan. I was nearby when the boss died.
Did I need to be right next to the boss when it died? I was still in attack range(I put on Searing Moonlight to continuously hit the boss).
Here is proof of my damage and the lack of quest completion.http://oi57.tinypic.com/24b3n1k.jpg