This quest is no longer available within the game.
Slay Prince Sarsarun and inform General Marcus Jonathan in Stormwind City.
NPC #45214 slain
Is THAT what's behind the storms assailing my city?
Let's push on. That towering windbag can bellow and blow all he likes, but this is the end of him. Tell General Marcus Jonathan what's happened here when we've gotten back; I'll need to oversee the return of the citizenry, repairs, and so on.