Hello again Herbstkatze!
Some more links to complete his profile:
https://www.memento.wien/person/53710/
Siegfried Driller (1896 - 1944) - Genealogy (geni.com)
Brother: Leon Driller
https://www.stolpersteine-berlin.de/de/wielandstr/15/leon-driller
See for his sister-in-law Estera Jasgur (spouse of his brother Leon Driller)
Warm regards!