Alpha wolf quest not advancing

My friend and I slayed the alpha wolf twice. His quest was able to be handed in but not mine. My journal even says to talk to the farmer to advance the quest. The farmer tells me that the wolf needs to die. Thanks!

 

I had that problem too, just walk away a distance from the farmer, then return to him, and talk to the man.
My problem is that I was able to complete the quest, but I still have it in my journal that I have to slay the wolf, poor little wolfie !