> There is no way to refund a game acquired as part of a bundle.
Sure there is. Each person who purchased the bundle gets refunded the full price of the removed game at the time of purchase or the full price of the bundle, whichever is less. Itch.io does not remove the game until the developer has paid for the refunds. If the developer can't afford the refunds, the game stays up.
That should cover all cases except where the game contains actual illegal material.