I am not exactly sure where to begin with this. But I'll just jump in and see where it goes.
Do you happen to know if the physics classes were part of the reason for disenrollment? I ask because if the answer is YES, then the first step in that process would have been to issue him a letter of warning or place him on academic probation, followed by a more severe step of initiating a Leave of Absence (LOA) which would have removed his scholarship until he passed those classes.
If the physics class was not the reason for disenrollment, then whatever else there was, would have resulted in a Professional Review Board (PRB). If there was a PRB (and I suspect there was), there would have been an initial notification letter sent to him, which included explaining his rights, and then the actual PRB. He would have been allowed to submit documents, provide character witnesses, and make an oral argument in front of three naval officers which would have included the Executive Officer.
Then he would have been notified in writing of the outcome of the PRB, and given 5 days to provide any rebuttal on that decision. Finally the PNS would have reviewed that and forwarded it off to Naval Service Training Command. A flag officer would review it, along with a Staff Judge Advocate who would validate legal requirements were met (this includes proof of service to him....meaning the PNS had to demonstrate your son was properly notified and given sufficient time to respond.)
After all of that, considering there would be a need for recoupment of funds (or enlisted service), that package would be routed all the way up to the Deputy Assistant Secretary for Manpower and Reserve Affairs. The amount of legal scrutiny given to these things is, to say the least, ROBUST.
And for clarity, the decision for him to be disenrolled resides with Naval Service Training Command. The DASN role is to determine whether recoupment will be monetary or by enlisted service.
I feel the need to deliver a bit of "tough love" which I rarely do on here, but sometimes.......anyways. I promise you, you DO NOT have the whole story here. To assume that the Navy would simply not inform someone that they had been disenrolled, and just leave them hanging, it's just beyond the pale. If in any way this were true, then every senior officer at that unit should be dismissed. And so I will just say it......there is more to this story that either you are unaware of, or you are aware of and just prefer to ignore. But this does not hinge on a mere physics course that was eventually passed. The amount of work that must go into these disenrollment packages is hideous and NO ONE wants to do it if you can avoid it. And besides that, no one wants to treat a Midshipman that way.
If your son desires a copy of his paperwork, I suspect all he needs to do is call the unit and ask for a copy. If he doesn't want to call the unit, he could write to Naval Service Training Command and I suspect they would direct the unit to send a copy of the paperwork. As a separate note, anytime a Midshipman who was on scholarship fails to commission on time, there is a staff code at NSTC that asks for the paperwork, so it's pretty hard to hide the fact that someone was disenrolled.
And as for you or your spouse calling the unit for information, let me prejudge the answer from them. They will tell you that your adult son needs to be the one to make contact and request his information. Because it is privacy act protected and they cannot release it to you or your spouse. And for what its worth, the university won't release his grades to you either, under the FERPA act.
To be honest, I am writing this not so much for you but for all of the parents and applicants who wonder if NROTC really treats people so poorly. You won't hear me nominate any of us for sainthood, but you really, really need to sit back with a calm mind and ask yourself........does this make any sense? And then have that tough conversation with the young man and say.........OK.....Out with it........what is really going on?
I do wish you the best in this, and hopefully it settles itself out in the long run.