I think it honestly has to be. Oda even teased him here in Oden's flashback:
He's the only person with those eyebrows lol.
He's the only person with those eyebrows lol.
this is kurozumi higurashi admitting in that scene that she's an associate of shiki, who was an active member of the rocks pirates when that scene happened. in that same scene, orochi asks her if she's even a kurozumi, and she goes "that doesnt matter" because setting orochi up as ruler and giving him the devil fruit are so important for whatever reason. only after Rocks breaks up at God Valley and several years pass does Kaido show up here and back up Orochi.
so like, how long was this plan in place? is Kaido only here because of Rocks in the first place?