Think it's more bcs she killed a noble that he's worried abt her, cause yk.. could bring her danger?
He was literally talking about her posing a threat to the crown prince since she was capable of killing. If it was about her safety only, there would be no reason why it might be bad to tell Pell about it and be a reason for her to leave. He was worried for Pells safety and nothing else.
I mean if you saw a girl just kill a guy w ominous shit around, won't you be kind of yk... Maybe he just said that bcs of the situation and context of what he saw?
Why is bro so upset about the possibility of her killing someone??? They have killed quite a few people on this journey while this is the first person she has been shown killing. If just the fact that she killed that human trash makes him think that she could be a danger to Pell, then by that logic his entire group is dangerous to him and way more than she would be. Pell would also technically be a danger to himself XD