Just a clarification here ... only about 200,000 were captured at Stalingrad ... plus another 50,000 or so Romanians and Russians. The Romanians were German allies, of course, and had been trying to hold the German flanks while the Sixth Army was attacking STalingrad.
The Russians were called Hinis, meaning they were drafted by the Germans to do menial jobs like cooking and supporting the soldiers. They really had no choice and were slaves, yet Stalin treated them worse than the Germans. None of them would have survived long after the German surrender in February 1943.
A Hiwi ( Hilfswilliger ) was a foreigner who volunteered to serve the Nazis. The nameHiwis acquired a thoroughly negative meaning following Operation Barbarossa in World War II. Between September 1941 and July 1944 the SS employed thousands of collaborationist auxiliary police recruited as German Hiwis directly from the Soviet POW camps.