The only thing I couldn’t figure out is how this was his first “mission”. Then I realized he was likely in “A” school (or equivalent) right after basic for his rescue swimmer designation which would have kept him away from regular ops until now.
If he had 3 years of ROTC in HS he can go in directly as an E-3 then only 6 months is required to E-4....at least that was how it used to be.
He is older, appears to have had a bit of a career with KPMG as an accountant/