I didn’t know that the Marines stayed after Saigon fell.
Last Marine combat units left in 71 as Nixon Vietnamized the war. Unless he fid four years with the embassy protection detachment his claim is bogus. In 72 he would have been 17. If he graduated recruit depot and Scool of Infantry it would have been 73. Were rookies out of School of Infantry assigned to Saigon Embassy durpty? Unlikely.