In the end the Navy will make a choice based on the needs of the Navy. If Keenan does well in camp and it looks as though he will crack the 53 and receive substantial playing time, he is golden. He is worth his weight in gold if he starts. His potential as a recruiting tool far outweighs the impact any singular Naval Officer might have on the service. If he cracks the roster, the Navy will move him to the USNR (US Naval Reserve) and he will do his bit there.
The Navy learned with David Robinson. They lost him as a recruiting tool. The two year service requirement he served put him in the Navy's version the Army Corps of Engineers. According to the agreement, his service time was over (completely EAOS'd) after the two years. They could have had him as a recruiting tool for the full 5 year commitment of a Naval Academy graduate.
Cardona's waiver to play long snapper for Patriots after being drafted last year is the new precedent. Cardona spends his off-season doing recruiting tours/motivational speaking engagements. He will serve his entire 5 year Midshipman requirement - just not on active duty.
If Reynolds makes the 53 he is good to go - a certified NFL player. If he does not - it is time to strap those butter bars on and meet the fleet.