In the summer of 1944, the People's Uprising Corps () was formed with four regiments of older reservists under Metzger, by then a Major-General. The Corps, named after the original corps which fought alongside the Royal Croatian Home Guard () against Serbia in 1914, was disbanded in March 1945. Metzger then led the 4th Division in the Battle of Lijevče Field between March 30 and April 8, 1945. For his service to the Independent State of Croatia during World War II, Metzger was awarded the Order of the Crown of King Zvonimir 1st Class Cross with Star, which granted him Knighthood and allowed him the title "vitez". Metzger surrendered on 15 May 1945 to the British and was repatriated to Yugoslavia. Having been convicted as one of the chief organisers of the Janka-Puszta concentration camp in Hungary, was executed in Zagreb on 21 June 1945.