No one talked to him before hand so he's not really allied with the party. and even if he recognized the Iron Rose name haven't they long since drifted away from being a religious order? they'd just be any other group of knights to him.

point is he doesn't care right now, he's not out to get you but he's not going to ensure your safety either. And if it means destroying his target he'll go through you.

It kinda seems aligned with how reonite paladins are in this universe, highly aggressive and out to destroy evil, he's just on the extreme end of that.

...at least, I think