I would but in this chapter I don’t see him as a protective brother. I don’t think he would be willing to help them if he didn’t have any sort of attachment to her. The way he’s acting about “I lost her once” make it look like she was important to him since they haven’t said anything about why he was friends with her in the past then I assumed that he liked he and he will definitely be in the way of my ship.
Go back and read the chapter again and look at who he's talking to the whole chapter. It's not Adele, it's the duke. The only time she speaks is when she interrupts their conversation. This guy isn't being protective of Adele, that would be if he was telling her that she's going to stay with him. No, he's telling the duke that she's staying with him. That's possessive. He is treating her like an object. That does not deserve second chances.
I'm sure Jean is just being protective of Adele, I MEAN CONSIDERING THE FACT THAT HE HAS ALREADY LOST HER ONCE.. This is only my opinion but why don't ya'll just give him a chance? He might turn out a great guy than what ya'll are assuming now.
Again, this is only an opinion and suggestion :)