Pluto2 The thing is, he sees various future selves, not all of which are the ninth. The Merlin Doctor (redhaired) is seen, as is the Valeyard. And neither of those are a Ninth Doctor. From a narrative perspective, all we can say on the Shalka Doctor is that he's after his Eighth incarnation. He's had at least nine lives - given Warhol painted nine of him. But nothing narrative says the incarnation is the ninth outright, it's only implied.
And rather heavily implied too by The Gallifrey Chronicles