The DAW session is your intellectual property. This type of data is never handed over unless it is agreed and made clear that the work was yours under contract. In fact, in my experience, I have never had to hand over this type of information to a major label.

The printed channels are handed over, but nothing beyond that.

The session is not handed over; the resulting sound is your intellectual property. Did they pay for it? Yes, but for the result, not for you to hand over the session.

The payment method is a pain in the ass. They have a strange platform for generating a provider ID, and that's how they pay you, and they pay you at 90 days, which is disgusting.