In my most recent playthrough I finally managed to get the owlbear cub. I went to the goblin camp just to get him and planed to kill the goblin leaders later.
Well, after I had tamed the cub I finally got around to dealing with the goblins. I ended up not only killing the leaders but all the goblins and my first rest after that the cub has disappeared. Scratch stayed at his new spot but the cub was nowhere to be found despite having stayed there for several rests already.
Either this is a bug that needs fixing or it is a nonsensical and unexplained punishment for exterminating all the goblins that needs to be changed.
Murder hobos deserve owlbears too!