In my industry, (seagoing) many employers require physicals above and beyond what is required by the Coast Guard. Could it be possible that they found something disqualifying for this particular job? Many industries are physically demanding and the employers are keen to reduce potential workmen's comp claims. You may be healthy but if they saw something they were iffy about (and they really zoom in on back and knees), then there you go.
If the purpose of the physical was pre-screening, you probably signed something in that stack of paperwork they gave you that granted permission to release results to the employer.
If you can't get the results yourself, you might see if your own doctor can try...but nothing is guaranteed because they really don't have to send them to you.
Many government positions also include language that states that the medical is one of the last steps in the hiring consideration, but, that you can still be rejected should any potentially disqualifying information present itself even if not directly related to the medical. One does not generally have a right to know why they are NOT hired.
Thanks guys - that's where I was trying to go. Alas, my keyboard is stoned (aka sticky key syndrome)
Even with a treating physician you sign an agreement giving the dr permission to release your medical info to other healthcare professionals that the dr may consult and your insurance company and others. Very, very few people read every paper completely before signing it. Then they say they never gave permisssion. These papers are signed when you do the New Patient paperwork.