Yeah, they could end up banning Io to prevent OG from picking it. On like Saturday I believe, I was watching VP vs OG together with that person and OG had the Io pick first game too. In the 2nd game VP did end up banning Io, quite late though as like 3rd or 4th ban.
So I'm really curious to see if the other teams facing OG during the main event will frequently ban Io, perhaps even pick Io before OG can pick it, or what they come up with to deal with it.