Kammala jumla mai zuwa: Matsayin aiki na Matthews ya fara ne a watan Yulin 1943, sauka a Sicily da kuma jagorantar bindigogin jirgin ruwa na HMS "Roberts" kuma daga baya ya sami wuraren da ake amfani da bindigogi, yayin da yake karkashin wutar abokan gaba kai tsaye, don kai hari kan Agira a lokacin yakin basasa na biyu.
Yaƙin neman zaɓe na Sicily. A watan Satumbar 1943, yaƙin neman zaɓe na Italiya ya fara: daga baya aka ba shi DSO. Ya koma Burtaniya a watan Janairun 1944, bayan an tura shi zuwa II Canadian Corps a matsayin CCRA, wanda ake ɗauka a matsayin "aiki na biyu mafi girma ga mai harbi a cikin Sojojin Kanada". An kunna II Corps a Normandy a ranar 11 ga Yuli, 1944 kuma ya shiga cikin ayyuka da yawa (Aikin "Atlantic", "Spring", "Totalize" da "Tractable") a cikin Yaƙin Normandy. Matthews ya ci gaba da shirin harbe-harben bindigogi ga kowane ɗayan waɗannan ayyukan.