ZKK will happen.
Kaido has been fighting his entire life and so far nobody has been able to kill him. He was hoping the Scabbards would the strong samurais capable of killing him but he was wrong. He said only Joyboy can beat him. Even if you consider this a win for Joyboy (Luffy), Joyboy couldn't kill him.
Kaido won't change his goal or character just because this defeat came from Joyboy. In Kaido's mind Joyboy should be just another opponent who didn't live up to his expectations because he wasn't able to kill Kaido.
I wouldn't be surprised if Kaido truly believe he's invincible since Joyboy couldn't kill him. Either that or Kaido considers the Joyboy legend just that, a legend.