I'm just saying when he defeats Kuzan in the future and/or helps Luffy defeat Blackbeard as a God Valley parallel I don't want you to look like a complete fool for doubting him. I'm trying to get you on the right path here
The Coby fight will be against Pizarro. The hero saving the slaves from the Corrupt King, the fight that Oda set up by making Pizarro be the reason Garp stayed behind, and being the only BBP Coby interacted with in their camp.
coby vs Kuzan is Coby vs Boa 2.0