WotLK Death Knight zone bug?

[HClGamer]

Hello,
I'm having trouble in a Death Knight zone, i took a quest from Thassarian called "Brothers in death", and i abandoned it at a point where i killed the dude that jumps you because i forgot to loot his head, and now i cant retake the quest Thassarian wont give me the quest again, I'm playing on icecrown, any suggestions on what to do, i really don't want to remake and redo the whole thing again.
Thank you.

[HClGamer]

problem solved, im dumb.