"No outside readings. When the Vault sealed, all contact with the outside world was cut. Nothing to even hint we're down here."

He sounds oddly proud of that, despite the fact totally cutting themselves off from the surface was, in hindsight, likely a bad plan.

"Mission plan was Vault-Tec would update us when it was safe. But there's been nothing from HQ. Guessing the damn Red's took them out."