Why would Kizaru need to say anything. Everybody knows Luffy has CoC. Just because he learned to use CoC a new way doesn't mean every single character need to comment on it. Luffy knew Zoro had CoC and he didn't say anything.
Luffy not using CoC with snakeman or other attacks doesn't mean anything. You still haven't provided proof that was CoA.
Zoro said he would release all his haki.
Zoro's words: what do I do? I can only appease it if I keep going all out with my haki, but that will kill me! No... This is how it's meant to be!
There you go. Like I said just read the manga.
The scene showed us Zoro subconsciously release and coated his swords with CoC. Remember, Wano ws about us readers learning things can be coated with CoC. Looking at indicators:
- Zoro was releasing and coating his swords with all his haki.
- his swords are coated lightning, which is used to show a character's using ACoC.
- we see characters lose consciousness from the lightning that coated of his swords
- King asked Zoro if he wanted to be a king (conqueror)
- we have seen Zoro release overwhelming CoA haki multiple times and lightning has never been shown with his CoA.
You keep bringing up Ace scene like that scene is the same. If not, it's very different. Ace was about saving his friends. Zoro scene was about coating his swords with haki.