Your son sounds similar to my daughter who is just finishing up this process.
If he wants the naval academy, he should start that process now. The preliminary application is available. Also have him take care of the candidate fitness exam over the summer, and watch your representative and senators websites about nominations. Find the service academy forums on the web, there is a wealth of information there.
If he is interested in serving in the navy, begin the nrotc accplication as well. Ideally, he should have it completed for the first board in October/November.
After those are done, identify engineering schools, preferably with EA, because the academy tends to award most appointments after January. It would be problematic to be accepted ED and then receive an appointment. On your list, g’tech and MIT are ea. You may want to add Villanova (EA) since it has a great nrotc program. RPI has nrotc, and he should have a good shot there, unfortunately they are ED.
Your list is not that off. My daughter was accepted to the academy, MIT (Ea), Gtech (deferred, accepted rd), Villanova (ea) and a couple of others. Her requirements were basically an engineering school near or in a city with nrotc.
Good luck with the year ahead, and pack your patience, the navy does things on its own timeline.