The final battle will be between the 4 conquerers.
Oh, back to the stereotypes. Zoro ain't Captain and no CoC as of now so he ain't qualified.
You must be blind if you think Zoro will be less involved in Kaido's downfall than Kidd.
+ If Zoro unlocks Conquerors by any chance you will be laughed at.
I'm not trolling against Kidd. His situation looks way worse than Killer's who people laughed at for being at the roof. Meanwhile, he is doing boss job while Kidd wonders what to do.
Kidd is just unimpressive as a roof participant atm. He will have his shining moment but the main event of Kaido's downfall is for Luffy and Zoro. They are both heavily thematically connected to fighting and potentially defeating Kaido later on.
Kidd "just" wants to take revenge for his ass beating. Luffy and Zoro will be more important by default because they fight for the people of this country.
We will see how the situation turns out later on but you definitely need to open your eyes to some aspects. Don't be baseless like noodle.
If you wank Kidd do it properly and back it up by facts and the facts are that Zoro is more impressive than Kidd for the second chapter in a row.