According to the "Totenbuch" (death records) of Auschwitz III, Arnold Rood was murdered there on 13 May 1944. This date is a little different from the official date of death of 16 May 1944 as determined by the Dutch Ministry of Justice after the war. For the time being, the website joodsmonument.nl, list only the dates of death, as published at the time in the "Nederlandse Staatscourant" (Dutch Government Gazette) by the Ministry of Justice.
Death according to the “Totenbuch” (death register) of Auschwitz III
Official death certificate from Amsterdam nr. 371 for Arnold Rood dated 1 January 1952
Other sources from the website Memorial & Museum Auschwitz-Birkenau/Auschwitz Prisoners/