I would spend some time on www.e-publishing.af.mil reading AFI 36-2205. It talks about eligibility for flying training. It may not be a home run, but a good place to start at least.
Regardless of what the reg says, IMHO it would be better to attrite rather than DOR. At least you have a good explanation for it and can say, "I busted my ass as long as they let me, but ultimately boat flying wasn't in the cards" rather than, "I wasn't good at it so I quit"
It is not uncommon to find IFF/fighter FTU washouts in the AF heavy world. If you already have wings your chances with a heavy unit would be decent.