Follow your journal tips.
Now I don't really remember the precise way, I think that you need to visit and make a deal with the Witch, prepare an extra remedy. When the countdown in journal says so, you go at night to the wolves' den, where is the Alpha, and you get enemy Bernard. Lure him with wolf lures, defeat him and you will find him at the prison cell of yours (you need to build it and upgrade it). Then give brand new remedy and he's back.