Another point about the "Cave list" which is not generally known, is that it was not only a first class cabin list. The second half of the list was the second class passenger list, but no cabin numbers.
Mike, do you know what deck or cabin Esther Hart was in? If it was on D deck, then yes getting a passenger's name and cabin was very easy as a second class steward's body was found with tickets for the entire D deck section in second class. Undoubtedly these tickets were forwarded to WSL in NY, however as other items forwarded there, the tickets are now missing, and most probably no longer exist.
Is it known though that there was a complete cabin list for at least 1st and second class. Miss Isham's family obviously also contacted WSL to find out she was in C49, and then contacted Gracie, and probably Marschal too.
Daniel.