The only F G I can find of the right age to have served in WW1 was a Frederick George b abt 1888, death reg 1968 in Chipping Norton, Oxon. He may be the one (occupation chauffeur) who married in 1924 as a widower to Jessie Barbara McCallum and baptised in Mitcham, Surrey s/o as Frederick George s/o William Henry Albert and Lucy Charlotte Willers (father's name same on baptism and marriage record).