This isn't about a racist joke. This is about a guy being part of a white supremacist movement and organizing his life around it. There is a colossal amount of difference between those two things.
After reading all of what this kid has been involved in I can see that he would definitely be canned from a reasonable company, and should be pretty easy to expel. I still would be careful in how it's handled, as to not empower these types of people. Realistically I see these guys in this article as dangerous, but not in the way as some type of person capable of leading any sort of serious movement or legitimate action, but more like the Sandy Hook shooter. These are not mentally healthy people.
If I were the President of K-State I'd probably put out a statement something along these lines:
"I've been made aware by some of our students that a KSU student has been posting inflammatory statements regarding murder victim George Floyd on social media. An exhaustive discussion among thousands of KSU students did not reveal anyone who had heard of this student, despite this student's claim that he was an influential leader. A search of other social media activity by this student shows a history of other inflammatory, albeit extremely obscure and hard-to-find material. The nature of his social media content and delusions of grandeur make it clear that Kansas State must take action. It is clear that this student has significant mental health challenges, and it is up to us to step in and protect the most vulnerable among us like this student before he causes harm to himself."
Then I'd probably go pick up my Chris Doyle "go away money."