You can do that misguided gymnastics that HUR DUR prime GARP was fighting ROGER, but there's no reason for you to put SENGOKU above Kaidou. Neither GARP and SENGOKU have any lines of speech in this manga placing them above Kaidou is the other way around.
You jobbers should prove Kaido is <= to Gb first
Then you bring up legends like Garp & Sengoku