The date listed here is incorrect.
Asser appears in the Auschwitz Leichenhalle book, which per Auschwitz museum's website, indicates: "Leichentrager kommando was responsible for taking corpses of dead prisoners or prisoners killed in the camp hospital, prisoners shot against the Death Wall, prisoners hanged at the assembly square or prisoners who died in residual blocks to the mortuary located in the basement of Block 28."
Asser's prisoner number was 71038.
You can view the source for this information here.