Game share works with Shadowkeep. In the event you are still searching for a refund, you are out of luck. Bungie has nothing to do with refunds, and Sony's refund policy is extremely strict and they do not stray from it. If you downloaded the content, any chance of a refund is gone. I found out the hard way about their shitty policy when I attempted to download a game to play in VR not realizing the VR version was a completely separate game and not just a different mode within the game. I didn't see anything to play VR when I started up the game, immediately closed it and contacted PS support. They told me once it is downloaded, that's it.