Hello,
It depends what documents you have received. You state you have his pouch, if correct this should have come from BT 372 at Kew and is not his full service record which should be his CRS 10 held in BT 382. Can you clarify what year he aboard ATLANTIAN (149686)? If you wish to give his name, date, and place of birth I could perhaps advise.
Regards
Hugh