NAH but why is it so important that he comes out? You seem to have a very narrow view of what coming out can be like. The worst outcome isn't "they do not want to go or refuse to meet you." The worst outcome could easily be, their entire family hates you, he gets disowned, he's never spoken to again, he's disinherited, and he's treated as if he was never born.

Obviously, you know more than we do, but I feel like you should consider the potential ramifications of what will happen if he comes out. You might have a different assumption of the range of possibilities that can happen, which might lead you to thinking that it's fundamentally a smaller issue than it actually might be.