At this point I assume all admirals have adv CoC, ofc not on the level like Garp but I think they will pose it alongside with awakening. Akainu perhaps will also have a insane adv CoC.
No, and I'll explain it:
Admirals have to report and obey directly to the Celestial Dragons. Garp didn't want do be an admiral because he DIDN'T WANT TO OBEY. He wanna be independent.
This is a clear sign of having Haoshoku. Although, I think that Akainu is going to have this (dude is an exception).
Haoshoku is always linked to this strong sense of freedom, like Garp has, Luffy has, Roger had, etc.