Why not?

Just tell him u want jim to use u too

My name is Gary and I would love to fuck your wife. I hope her name is CIndy a I would love to fuck CIndy! Eat her pussy with you watching.

It sounds to me like this Gary has already fucked your wife and made her cum when you couldn't. The problem seems to be that you wish you had been there when he did her. Obviously you have a thing for this Gary, either finding him extremely attractive. Or that you think he's so much more of a man than you and you want him to humiliate you while he's fucking her again. You may have to clarify this more in your story. Either way you want him to fuck your wife again. Why not just talk to him. He doesn't have to be gay to dominate you or make you watch while he fucks your wife. And if I've got this all wrong and he hasn't fucked you wife yet, if he's as much of a hunk as you think he is, maybe she'll be happy to have him fuck her. Whether you're around or not. You might get some wet cum soaked panties to suck on when he's done with her.

I'd suck on a lot more than panties