Are you sure Kabuto was Orochimaru's teammate? I think he was in Konoha undercover for his whole life.

I think that Orochimaru had another team mate instead of Kabuto.

Their are 9 of them, so that would mean one of them didn't have a partner. I always assumed the head of the organization wouldn't have one. I don't know how the organization is now since he left and they are back to 8, unless they got another person to join.