Is this in bad form? What does the guy have to do to convince you that he has to rename the library? It's tough cookies, but if he renames it, and the Redis Ltd. people fork the library and put the fork on crates.io under the redis name, that's what happens. The way it works just isn't whoever gets the name on crates.io first, irrespective of copyright.
I'd think that if the situation were reversed - Random Guy On GitHub Complains About Distasteful Actor Taking Over His Trademark - you'd root for the guy no?