If the student has posted or said things that are clearly racist, that would be grounds for dismissal. This joke wasn't that. This is a power play by the athletes to suppress other's free speech.
Do some research on McNeil. The joke doesn't exist if George Floyd is not a black man. It was 100% a racist joke.
In my opinion hate speech is free speech in the sense that nothing McNeil were to say, however hateful could land him in jail. But obviously all speech has consequences.
I don't know what KSU should do, they're in a tough spot. But if the administration is being honest then they have to acknowledge that if some football players want to boycott that is their right, also...whatever consequences come of it.
I think if I were the KSU president I'd make a statement condemning McNeil's statements and associations and make it clear that they're antithetical to KSU's mission. Basically I'd say (without saying it) that "we have to let this douchebag go to school here but he doesn't belong here."
Now, if I were the football program I'd put this kid on blast. I'd make it my mission to make sure every season ticket holder know exactly why any players might be boycotting. And the answer would be simple - Jordan McNeil. If the KSU football program is smart they'll embrace the players who boycott and direct all their energy to making KSU a place where Jordan McNeil doesn't want to attend school.