If it looks like Braggi isn't taking any lasting damage from his axe (for some reason, like if he's a were-creature), Brak will switch over to his magic javelin and stab at his opponent. If that looks like it hurts him, he'll pull out his magic dagger in his other hand and dual wield them.
Since the party has been together for a while, I think that they'll be aware that Levanna is not very good at lying and deception. So it's probably best if someone else attempts those things. Hopefully her lack of skill in being subtle will help to sell the idea that she's a naive first time slave buyer.