Tinnitus and hearing loss are common afflictions for SCUBA divers, both professional and recreational. If you ever had a pulmonary inner ear squeeze while descending, you have stretched that membrane until it bleeds inside. The pain is awful and you can't hear for days out of the affected ear(s). There was a study done, I believe I have the PDF on my computer. You can also get this from breath hold diving and some flyers get them. Google Valsalva Manuever.
They can go to the nearest military baseHQ and ask for the CACO, I think it stands for Casualty Assistance Officer. It's typically a collateral duty for an officer on staff. If they don't have one, ask for the Command Master Chief (Navy & Coast Guard), Command Seargant Major (Marine Corps & Army) or Command Chief Master Sargeant(Air Force), depending on the service organization. They are all trained and honored to help.