This is where I am, having read all the discussion I circle back here because this screams volume about him, the assumptions that he's making about her and her motives, and about what he's entitled to -- not contribution to offset additional expenses he has when she stays at his place, but specifically a piece of her AirBnB income -- paint a pretty awful picture of him.

Unless he has some evidence that she manipulated him into inviting her to spend weekends at his place, or refused to alternate weekends with him so that she could make more money, they aren't permanently cohabiting, and aren't commingling finances yet, so her AirBnB venture isn't really his business, and he's tipped his hand trying to claim that it is.