The total number of foreign German communists in the USSR in 1942 that had survived arrest in 1937-1938 was rather small. The Comintern had a list of registered members for foreign communists in the USSR in 1942 which included 131 members from Germany, 74 from the Austrian party, and 44 Sudeten Germans with membership in the Czechoslovak party. Other communists from countries at war with the USSR included seven from Finland, 76 from Hungary, and 57 from Romania. The Comintern officially asked the NKVD on 20 November 1942 that these party members be excluded from service in the labor army even though some had already been mobilized by this time (Krieger, fn. 66, p. 162). A number of communists from Germany, Austria, and the Sudetenland spent years in the labor army in various NKVD camps (Krieger, p. 151). The existence and persecution of Sudeten German communists in the USSR is particularly interesting. If nothing else their existence proves that the Czech claim that all Sudeten Germans were Nazi sympathizers was simply not true. Their opposition to Naziism, however, did not spare them from persecution at the hands of Benes's Soviet ally.
Source: Viktor Krieger, "Patriots or Traitors? - The Soviet Government and the 'German Russians' After the attack on the USSR by National Socialist Germany", in Karl Schlogel (ed.), Russian-German Special Relations in the Twentieth Century: A Closed Chapter? (Berg Publishers: New York, 2006), pp. 133-163.