Further to my post regarding Elizabeth's brother, George, and whether there would be any clues in his Will - I failed to notice this was an "Administration", so there is no Will.
However, I did obtain a possible death certificate (one of two for Elizabeth Allum of about the right age) and that came yesterday (after only ordering on Tuesday, incidentally, from GRO - two days, fastest so far).
Elizabeth Allum died on 11 December 1927 at 12 Exmoor Street (Kensington, I assume, as that is the Registry), which I think is the St Marylebone Hospital. She is "Widow of - Allum, occupation unknown" - so that fits with all the mystery and no-one knowing who she was, ie no family around her. She lived at 3 Daventry Street, NW1 - as did the informant "R Holland". The informant's name is followed by "Causing the body to be buried". Is this a standard wording? Could R Holland have been a landlord, perhaps? Who didn't know anyone else to deal with Elizabeth's burial? I haven't found an "R Holland" at 3 Daventry Street on the 1911 or 1939 records, and wondered if there is another way to find him/her?
Many thanks for any pointers and thoughts on the "Causing the body to be buried" comment, particularly by someone who lived at the same address (not a solicitor, or other "official", etc).