The one who landed the last blow and is the reason. Why the other is out ....is the winner
Katakuri even tho he actually stalemate luffy didn't get a W or Stalemate from Oda eyes despite everything : conscious, standing, talking, landed his finisher on luffy at the same as King Cobra.
But I should believe Kizaru who got rocked down, managed a win or stalemate because g5 ran out? Yeah sure
Keep lying to yourself