Thanks for your comments everyone. He gets that a switch to pilot is a slim chance but he had it in his mind that he was doomed for the remainder of his career and I was having a hard time believing that.
Doomed? No. As others said, API is a very minor part of your overall NSS and PT score is a minor part of your API grade. It won't impact his platform selection at all.
However comma. I was an API instructor for a few years and sat on quite a few boards, and when you have a bad day academically or flight-side, the less pink in your record, the better. Especially failing stuff like PFAs. It's the difference between a board/skipper/commodore looking at your jacket and thinking "seems like a good student who just had a bad day or isn't quite getting a concept" and "what a dirtbag".
Yeah, yeah, I know...heat and humidity and the NASC chip trail sucks. It's still a requirement and has been since the Earth cooled. What happens is, kids finish the Academy or OCS or whatnot and drop their PT regimen, because the Fleet standards look so much easier than wherever they commissioned. It doesn't take but a few months of beer and Gulf Coast fried delights and no gym before those Fleet standards suddenly become a lot more challenging. I speak from experience on that one. I remember huffing my way around that chip trail in August when I was an API stud, going "what the hell's going on?" I passed, but it wasn't pretty.
So let this be a wakeup call for your boy. I'm in most things all for the philosophy of "if the minimum wasn't good enough, it wouldn't be the minimum," but not in flight school. He should try to crush everything he can crush, because there
will be bad days and rough spots, and reputation proceeds you.