I think one of the strongest points behind ZKK/Zoro Kills Kaido is that Zoro is clearly racist: Kaido isn't only a non-white individual, he's also from a non-human-race, an Oni: that's like a wet-dream for Minority Hunter Zoro. Kaido better not think he's safe just because he's in a volcano. Zoro has almost cut his legs off to kill Mr. 3, a proud... um... Mr.3ean.
Zoro is CLEARLY willing to die by jumping into a volcano to fulfill his vile prejudice and kill Kaido the Oni, IMO (/s, just because ya'll take shit too seriously)