It's not just COA for King.
Zoro vs King's fight had a final clash of attacks.
Zoro cut through King's Imperial Dragon, which should count as part of King's defense since Zoro has to strike the Imperial Dragon before he can reach King.
So poll should be,
King's CoA defense + Magma Level Fire Dragon Attack
VS
Queenβs Branchisaourous + Cyborg defense