... except that it doesn't do much good.

Results are a little interesting. If you google "gender dysphoria amnesia" or "gender identity amnesia", you'll find a raft of links to dissociative identity disorder (what used to be called MPD, multiple personality disorder).

It sort of follows, especially considering the diagnostic criteria that the gate-keepers enforce. To get the letters for surgery, often even to get the 'script for hormones, you have to show the pshrink evidence of long-standing issues, preferably back to childhood. Which Charlie had, after all. By the time Stella knocked him off a bike in a storm, he'd already taken a number of steps. So the Charlie in hospital would presumably be one from some time in the deep denial period, when as a matter of self-defense he utterly rejected all thoughts and feelings that didn't match the male role to which he was assigned, a period in which he also attempted to suppress older memories.

That's not quite a dissociated personality, but an argument could be made for it, perhaps.

One would think that the shock of learning of his (her) parents' deaths would tend to undermine that return-to-denial, though. For this particular case, presumably the amnesia is a return to a state of stark, unbending denial (based on the story outline so far). Under those circumstances, one would also imagine that Cathy's current physicality would be deeply distressing. It might even be that, as a coping mechanism, Charlie-in-denial would insist that this was 'all a dream' (or nightmare). Gonna wake up, and be back just starting university, with everything locked down and tidy. Just a bad dream ....

Amy!