Nice to meet you, Barney. Welcome to cruise-chat, from another ocean liner aficionado.
That was so kind and generous of you to donate your family's mementos from "Lizzie" to Cunard. I was just telling my Mom yesterday (regarding something else) that she should look into donating years of photos taken inside a once vibrant building that is about to be torn down. Better to give them to a historical society than to sit in a box in her garage.
Back to Lizzie... I have a close friend who spent a large part of her childhood crossing the oceans on liners with her parents, and Lizzie was her favorite. This would have been a little later than when your wife's grandmother was onboard. I love hearing her stories about Lizzie and the other liners on which she sailed.
My family and I did a westbound crossing on Queen Elizabeth 2 in 2003. It was fantastic. There's nothing like leaving the world behind for a few days, not just forgetting what day it is, but what year it is!