Nope
Zoro was not feeding all of his haki to enma thus enma was absorbing Zoro's haki untimely
When zoro realized that he is doing wrong then he unleashes all his haki.
AdCoC was unlocked not for Emma but for king because all 3 of his swords are coated with CoC and not just enma
His swords being coated means nothing
Because of enma , CoC was unleashed
He never sat and said "I need to To gain more power to beat King"
The whole battle was him trying to figure out King's race and weakness, and mainly how to tame Enma
Luffy personally wanted and got fs to combat Kata
Zoro got coc to tame Enma. King is an afterthought
If Oda wanted Zoro to get CoC to beat King, he won't make the whole chapter about Zoro trying to tame Enma but rather zoro trying to figure out King's weakness and says I'm gonna surpass you or whatever.