It's been proven multiple times. Obviously, these types of cash rewards are just bluster, so they're never going to pay the money. If anything, Kues should be the one to receive it, because he was the first one, to my knowledge, to prove that the Theresienstadt trains that ended up in Minsk/Belarus were transited through Auschwitz and Treblinka.
I'll recap some of his arguments below.
In October, 1942, five trains departed from Theresienstadt with the designations Bt, Bu, Bv, Bw and Bx. These transports have been the subject of some controversy because everything about these trains points to them being directed to Treblinka. In fact, we know with certainty that at least one train from this convoy ended up in Treblinka because famous Treblinka witness Richard Glazar was on one of these transports. He was selected for labor deployment when his train (Bu) stopped at Treblinka, and he later survived the war. Orthodox Holocaust historians such as Miroslav Karny insist that these transports were all exterminated in Treblinka, but historian H.G. Adler changed his mind in 1974 and claimed that these transports ended up in Belarus. He wrote (from Kues):
"On 8 August 1942 a certain Dr. Engineer Jacobi of the General Management Office East [Generalbetriebsleitung Ost] of the German Reich Railway [Deutsche Reichsbahn] wrote to inform the Main Railway Offices in Minsk and Riga, the Reich Railway Head Office, the General Office of the Eastern Railways [Ostbahn] in Cracow and also the General Management Offices in Essen and Munich about the ‘Special trains [Sonderzüge] for resettlers, harvest workers and Jews in the period from 8 August to 30 October 1942′. To the cover letter was attached, among other things, a ‘circulation plan’ [Umlaufplan], which was later partially revised. The following trains, which were supposed to carry each 1,000 people, were assigned for the deportation of Jews (the declared destination Wolkowysk indicates Minsk)."
Adler's primary source for "extermination trains" arriving in Belarus is Isak Grünberg, a Jew from Vienna who was deported directly to Minsk in one of the rare direct transports from Germany to the Occupied Eastern Territories. Grünberg arrived on October 9 or 10, 1942, and described seeing numerous trains arriving with more Jews in Minsk despite the fact that orthodox historiography claims only 2 more trains were routed directly to Minsk from Germany after these dates, one on November 18 and one on November 28. So how is it possible for Grünberg to have witnessed the arrival of numerous Jewish deportation trains in October? Grünberg even expressly mentions Jews arriving from Auschwitz and Theresienstadt, "and probably other camps". The mention of Auschwitz is significant because it's a testimony of Jews in the OET arriving from Auschwitz (one of the "extermination camps") at a time when the camp was supposedly exterminating Jews wholesale in Bunker 2. The fact he mentions Theresienstadt is also crucial, because the abovementioned five Jewish deportation trains left Theresienstadt on October 5, 8, 15, 18 and 22. All supposedly ended up in Treblinka. But did they really? The trains Grünberg saw after arriving in Belarus on October 9 or 10 must have been routed through either Auschwitz or Treblinka and came from Theresienstadt, just as Grünberg mentioned.
Whether or not it's possible to name individual Jews from these trains I do not know, but that was hardly ever the point.
More from Kues' study:
https://codoh.com/library/document/evid ... st-part-2/