This was discussed pretty much in the ep 92 discussion. Anyway, it's pretty obvious that
it's the real Kabuto and not some illusion made by Tsunade, also, Orochimaru says
"Have you come here to betray me, Tsunade?" so she was probably not going heal
him but hurt him instead so Kabuto stopped her. That's what I think, and I'm pretty sure I'm right ^_^