I've used the dispel potion on the Leopard Girl, I've talked to the leader about getting the horn, but I seem to be stuck. I can't give him the horn and she won't take any of the items.

What class are you playing as? I think the horn means either a fighter or a paladin, which will trigger the Simbani Initiation, which I think should be doable by talking to the chief, leaving the hut, and returning with the horn. If you are playing a mage or a thief, the horn is not needed at all, you just have to pay her asking price.

Just did this with a Paladin, I can confirm you need to leave and re-enter the hut to give the horn and the bride price, seems to be scripting issue which re-entering the room fixes.

I'm a Paladin, I left the hut, brought him the horn, but he won't accept it. I also have the zebra skins and the others items.

Hmm. Did you talk to him about all Dialogue options? those may be triggers for this as well. I was always polite with him (greeting, saying goodbye) not sure if those directly affect things. You do need to become a member of the Simbani tribe first as a fighter/Paladin before you can pay the bride price.

Yeah, I was polite and tried every topic. This isn't the first time I've played this. Although frankly I thought 4 was much better, particiularly if you have a Paladin.