We simply have to find out what happened in this man's case.
I will say, I like the fact that he changed his name from Don to Dawn to Don again. If nothing else, he spared everyone the hassle of having to call him some brand new name.
Of course, it's a single case and who knows what variables are at work in it (scientists should really be trying to find out), but nevertheless... here a man was cured of an illness. He thought he was a woman, and then suddenly he no longer thought this. Quite the massive change in brain chemistry if his story is legit. Naturally, no one can call him 'cured' - that would cause outrage. Better yet, in articles, the man spends some enormous amount of time reassuring everyone that he's still totally on-board with the LGBT movement - gay marriage and everything. In fact he comes across as so obsessively repeating that that I wonder if the temporary spate of amnesia is just a lark, on the grounds that waking up one day and realizing 'I want my dick back, this sucks' is a situation no LGBT adherent wants to recognize as event remotely possible.
It reminds me of this case of a lesbian Arizona politician deciding that she likes men after all. Apparently she thought she was straight, then bisexual, then a lesbian in college - and then a pansexual. Of course, downplayed by all media sides was the fact that a lesbian suddenly included 'men' in her list of objects of sexual attraction, or what this means when a woman that old and in that liberal of an environment can either A) still be confused about her sexuality, or B) literally change it. But that would be quite an awkward conversation, so instead we have to pretend she 'came out as pansexual' and entirely downplay that this makes her an 'ex-lesbian'.