https://southpark.fandom.com/wiki/The_Big_Fix

Maybe someone who is more hip and with-it can explain it for me, if there is a joke at all. In the episode it is revealed that Token's name was always Tolkien because his dad liked Tolkien's books. Apparently everyone but Stan knew that.

Stan feels bad for being "racist" so he tries to help Token/Tolkien by making LotR required reading at school. The reveal is that Token/Tolkien hates the nerdy Tolkien stuff. This is obviously a dig at SJWs for misguided activism but at the same time forgives them for being "sincere".

There is a Dr character directly lecturing the viewers that if they thought the name was Token that they are horrible racists, that may be the writers apologizing for the original joke?

The meta joke, imo, is that with the reveal Token's name is being changed everywhere, including the wiki article I linked, 1984 Ministry of Truth style. And that is funny in a nihilistic, laugh at the burning world, kind of way.

The B plot of Randy needing a black business partner to show "equity" so he takes on Token's dad as a literal black token is more straightforward.