I've traced Elizabeth's origins, she was born in Waterford, Ireland. I also have her death certificate, with cause of death as "Due to War Operations", whatever that means. Edith Beckinsale claimed the body for burial.
Elizabeth's link to the Beckinsales appears to be that in 1911 she was In Service in Winchester, next door to where Edith Beckinsale, nee Goodall, was in service.