I don't understand this debate because Oda should made things clear.
I'm not saying Zoro do not have Conqueror's haki, I believe he has it, so DON'T JUMP ON CONCLUSIONS (yes, I'm talking to you Zoro fan)
BUT you can't argue that Kaido's words are pretty confusing about Oden's presence (he's clearly talking about his energy, his haki) when he saw Enma. Add to this that we discovered in Egghead how object can used to store haki for years and you have the first doubts.
So for me the hypothesis are three:
1) Zoro has king's haki;
2) The king's haki is coming from Enma so from Oden;
3) Zoro has king's haki but Oda is not showing it again for some reason, maybe waiting for some moments (Sanji's CoC reveal?);
I believe in the first one, trust me, BUT the other two are still a possibility. And it's hard to deny it with the info we got after.