You need to find him down in the druids grove first before he shows up to your camp, this is what Halsin means by unfinished business so go see if you can relocate him at center of the grove, normally you'll run into Halsin there showing his anger towards Kagha, if she's left alive.
If this doesn't help and you don't see Halsin in your camp party event, I am curios to ask, did you deal with all three goblin leaders in one single run without any long resting?
-edit- Reason I'm asking is if you choose to use non lethal method with any of them like Minthara, you might want to double check by a revisit to goblin's camp to make sure all three of them remain dead or re-doing them without long rest inbetween from an earlier save.
But I am not entirely surprised if something could have bugged out for you, when it comes to Halsin disappearing and not showing up neither in the grove or later in the camp party after initiating a long rest.
Last edited by Xenonian; 16/04/24 12:46 PM.
