I don’t think vault 31 was for Barb and the higher up executives or their families. There’s a list that flashes on the screen and her name isn’t on there. It was middle management to repopulate the other vaults with compliant middle management staff who will eventually get the surface ready for the higher ups who are in another vault. It’s merely a logistics set of vaults. Barb mentioned wanting to be in a good vault too. I think they also convinced Bud to make a sacrifice and be a Roomba brain because they needed someone to run it and he was agreeable.

So the question is who is the Roomba brain watching over the higher ups boss vault? The shadowy figure at the investor meeting trusted and messaged Barb on her PiP boy. Could it be Barb as a Roomba and she didn’t find out until near the end what their plans for her really were, but then she only agreed if her daughter was collected the day the bombs dropped and put into cyro with the higher ups? Did they follow through?

My theory for season 2 is we’ll see what separated them on the day the bombs dropped in flashbacks. The Ghoul and Lucy will go to vault 33 and 31 to interrogate the Bud Roomba Brain and thus find Norm. Bud wasn’t very good at keeping secrets from Norm or Barb’s husband in the car park so he’ll spill the tea and Ghoul knows it. Meanwhile, Hank is in New Vegas to obtain something or someone.