Gaban told him what's going on.
You’re thinking from an outside the story perspective. Matchups are almost never set between that many characters ahead of time
They’re usually obvious to us but outside of Luffy (who usually verbally states that he’s gonna fight X) they just happen
Enies Lobby, Alabasta, Wano, Skypiea, etc
They “randomly” engage their opponent and the fight goes from there. You can predict who will fight who based on the narrative but Oda never locks in matchups the way you’re thinking
I highly doubt that’s gonna change now



