Yeah, I’m also wondering how much of the characterization of his mental state is down to the people around him describing the situation rather than his own description of what’s going on. (Not that he’s a reliable narrator of his own fractured mental state, either, if he’s suffering brain damage.) He’s creating workable fictions to have something to grasp hold of, and those are further being turned into neater narratives by those around him trying to understand - or report on - the situation.
And apparently the source for this story is The Daily Mail, so even if it’s actually (vaguely) based on fact, and they didn’t fabricate it entirely, they’ve created another layer of fiction divorced from what’s actually going on, that better fits fictional depictions of amnesia. So gods only know what the real story is here.