Thought it was a pre-requisite!!!
Sorry, I couldn't resist that; inter-service rivalry and all that nonsense!
Seriously, only ONE doctor has made your diagnosis? Get a second opinion but not until you have all the facts which can be gleaned from the military medics at Cranwell. If you want to do it anonymously, get your mate who doesn't want to join the RAF to write on your behalf.
My flying career was nearly over a couple of years ago because of poor wording on a diagnosis.
What they had meant to say was that my symptoms (which turned out to be an unexpected side effect of medication) were similar to XYZ but their wording insinuated that I suffered with XYZ.
This meant I had to go for private consultancy (luckily for me the consultant understood the balls-up and did the hospital tests on the NHS and saved me a small fortune) and obtain a very carefully and ACCURATELY worded private report.
It still cost me a fair whack - not much change out of a Grand!!