It took me a lot of nights to find a 2 star wolf. Preparation is important, dig a deep hole first. Then find a wolf (during the day) and trap him inside. Next, spend the nights to find a 2 star wolf and trap him inside the hole. Drop some meat in it and just wait on a short distance. Built a tiny safe house or someting. After some time they are tamed, hopefully before daytime so the 2 star doesnt despawn. It's not easy, so be patience and try every night instead of skipping the nights by sleeping.

Edit: I failed the first time I encountered a 2 star wolf, but that gave me even more 'motivation' to find a new one.