Since the birds scattered after the shot,Why didn't ya just call em back?
LOL. I have only been learning about this fall hunting stuff but that was my first thought. He just scattered the birds for the exciting part of the hunt to begin. I guess if you're scattering them you could shoot one while you're at it.
The other side of the story is always crucial but it does sound weird. I would say he broke HIS side of the contract based on what you have told us. No reason to pay him. If you are still thinking you should pay him I would wonder what more we're missing here.