Kammala jumla mai zuwa: A cikin 1940, Gaynes ya zauna a Faransa, amma bayan Yaƙin Faransa da aikin Jamus, ya tsere zuwa Pyrenees, amma ba da daɗewa ba 'yan sanda na Francoist Spain suka kama shi. A cikin 1942 bayan an sake shi, Gaynes ya yi niyyar komawa Netherlands don shiga cikin juriya na Dutch a kan aikin Nazi, amma a maimakon haka ya yi tafiya zuwa United Kingdom don shiga cikin Royal Dutch Navy. A ranar 8 ga Afrilu, 1943, an ba Gaynes aiki a matsayin ɗan jirgin ruwa kuma aka sanya shi zuwa jirgin ruwa mai taimako, wanda aka ajiye a Holyhead a Wales. Saboda ilimin harsuna da yawa (yana magana da Yaren mutanen Holland, Ingilishi, Faransanci, Italiyanci, da Rashanci), an raba shi a ranar 1 ga Mayu, 1943, zuwa Royal Navy a matsayin mai fassara da aka sanya wa kwamandan jirgin ruwa, wanda ya halarci Yuli da Agusta 1943 a
Operation Husky mamayewar Allied na Sicily. A ranar 1 ga Satumba, 1943, an sake sanya Gaynes zuwa jirgin ruwa, wanda ya shiga cikin watan Janairun 1944 a yakin Anzio. A ranar 1 ga Janairu, 1944, an ba shi mukamin sajan (sabon jami'in, aji na 1). Bayan yakin Anzio, an sanya HMS "Wilton" zuwa Tekun Adriatic kuma ya ci gaba da ganin aikin a lokacin yakin Adriatic. A ranar 14 ga Yuli, 1946, Gaynes ya yi murabus da girmamawa daga Rundunar Sojan Ruwa ta Royal Dutch.