Okay; in fairness, if diving was part of his military job, he may not have needed certification from an outside agency. While the UCMJ applies equally to ALL branches of the U.S. Armed Forces, the code that was citied referred to recreational diving.
While I imagine a Navy SEAL or an Air Force PJ or their analogs in the other branches would have no problems whatsoever passing certification requirements with any dive training agency, I doubt Uncle Sam is going to hold up their mission performance if they don't get their PADI OW card before deployment.
Ergo, while I cannot say that Scuba Dew is telling the truth, it seems to me it would be possible for him to have logged dives in the military before getting his civilian certification.
Just as a personal observation aside, when our cruise ship returned to San Pedro, California, at the end of our cruise last year, two or three boatloads of divers showed up next to it, from a couple of different law enforcement agencies. Since the ship had visited Ensenada, Mexico, I figured these divers were inspecting for anything possibly tagged onto the hull of the ship below the waterline, such as drugs, terrorist weapons, or bootleg copies of Ishtar.