Records for Robert E. Yensan, shipfitter 3rd class, Navy Reserve

Can anyone tell me how one might obtain records for a Navy Reserve shipfitter 3rd class named Robert E. Yensan who died 1/1/1945. He is listed on Fort William McKinley, Manila. Not much is known enough about him to even get a death certificate and without death certificate, cant get military records. Can anyone tell me what should be done next? Am searching on behalf of his daughter who never knew him. Thanks.