This quest is not available in game.
Confront Ulathek, then bring The Traitor's Heart to Lord Banehollow in Jaedenar.
You wish to enter my good graces? Then kill for me.
My servant, Ulathek, is pathetic how he grovels before me, all the while plotting with Lord Hel'nurath on Xoroth. Hel'nurath plans to usurp my power here, and Ulathek is his spy...
Prove that you serve me and not my rivals. Confront Ulathek in his quarters, in the Shadow Hold to the west. Tell him that I know his secret and watch as fear grips him. Then, bring me the traitor's heart!