I wish I could help. I never actually found him; he just showed up at the Grove after I wiped out everything in the goblin camp and went back to sell everything before actually looking for him.

I will say that sometimes you can just reload a game (doesn't have to be an earlier save or anything just save and reload where you are if you want) and it fixes a ton of scripting related bullshittery like this. Any time I notice a script failing to fire (like a line of dialogue not playing, or the enemies get stuck just standing around in combat never actually taking their turn), I quick save, quick load, and it's usually fixed.