Yeah thats what i thinking before, when kaido descend from the sky. The narrator said "if 1 vs 1, kaido will win".
So ill take that as if Whitebeard vs Kaido, Kaido will win.
Shanks vs Kaido, Kaido will win.
Big Mom vs Kaido, Kaido will win.
So, back in oden flashback, did he still gonna win without using momo as a hostage?