The date of is death, 15th july 1942, is however the date of the first transport to Auschwitz from Westerbork.
The Dutch Red Cross mentions:
"Heinz Feldman was born on 30th september 1920 in Vienna.
According to his file he was before 1939 when he came to the Netherlands, a prisoner of Camp Buchenwald.
On 15th july 1942 he was deported from Westerbork to Auschwitz.
After the war it was established that he was killed/died latest 30th september 1942"