I didn’t see an email address for you, so I am posting my response here. My paternal great grandmother was Miriam Konigsberg (born 1856). Her father was Gabriel Konigsberg (born 1830) son of Nathan Konigsberg (born 1800) who was the son of Simon Konigsberg.
I am curious if you have gone further back with your uncle’s lineage and I wonder if your family intersects with my family. Both my father and I are in GEDMatch as A198550 and A870426.