Early October 1943, a month after the arrival of the transport of 31 August and 7 September 1943 from Westerbork in Auschwitz with in total resp. 1004 and 987 deportees, among them possibly also Wilhelm Humberg, a group of 187 Dutch prisoners was formed who were deported to Warschau to clear the area of rubble of the devastated ghetto. Originally there was a group of 264 men, younger than 50 years, of whom 77 were killed in the gas chamber.
It had previously been decided to transfer the contingent of men, that had arrived from Westerbork on 2 and 9 September 1943 in Auschwitz, in their entirety to Warsaw. According to a subsequent finding by the Red Cross, all men between the age of 16 and 51 years, who had been deported to Poland with the transport of 31 August and/or 7 September, arrived in Warsaw via Auschwitz on 8 October 1943, where they have died before 31 March 1944.
According to the American historian, Gerald Reitlinger, of the mentioned transport of 7 October 1943 from Auschwitz to Warsaw, there were only 15 survivors. It has also been established that many prisoners of this Jewish camp in Warsaw died during a severe typhoid epidemic in early 1944. Among them were also many Jews from the Netherlands.
Wielek describes in his book “De oorlog die Hitler won” (The War Hitler Won) on page 381 that the cleaning of the rubble of the devastated ghetto lasted until 28 July 1944 under the most humiliating and beastly conditions. When the Russians stood before the city, the crematorium under construction was not ready and 600 sick prisoners, who could no longer walk, were shot to death and the rest had to march 120 km up to Kutno, from where they were transported to Dachau with 90 men per cattle car.
Wilhelm Humberg never experienced the latter. After the war, the Dutch Authorities formally established that Wilhelm Humberg has died on 31 March 1944 in Poland.
Source include a study, reports and testimonies as described in the book “Etty Hillesum in perspective”, edited by K.A.D. Smelik, Ria van den Brandt and Meins G. Coetsier. (pages 149-151). Editors: Academia Press, Ghent, Belgium. Also: "De oorlog die Hitler won" by H. Wielek, 1947 - Amsterdamse Boek- en Courantmij N.V. Amsterdam, pages 381 and 382 and certificate of death nr. 279 for Wilhelm Humberg-made out in Winterswijk on 14 December 1951.