Personally, the fact that he only has 1000 HP is very encouraging. And Kasha should always suggest the best course of action.
As for the role-playing aspect, it's even simpler – the fight is already underway, everyone wants to survive, and if you want to survive, you have to kill the enemy. Afterwards, you can go after Anders, argue, repent – but right now, when direct aggression has been expressed from both sides, only a very specific type of person would try to resolve things peacefully.
e si ieu muoir, er mi grans deliuriers