Seriously, I wouldn't even be mad at Kelly if she charged him a million dollars to perform, and then donated it to an LGBT charity, or BLM, or something.
It's NEVER going to happen. At best he'll have to settle for some b-c list country singer or band.
I think the best shot he has at an A lister is Kanye (I honestly do believe he's messy enough to do it if asked) but they wouldn't want a rapper anyway.
It can't be a big celebrity as it goes against his entire image as being anti elite/establishment. It would have to be some school choir picked from Kentucky or something.