It was never revealed as far as I know, but there would have to be a secret Vault Tech Vault with all the upper Vault Tech officials with computers monitoring the vaults. And most likely raising their children to takeover the mission when the elders pass or they are using cryostasis to stay alive. But it's a real good chance they are still watching the remaining vaults until all tests are completed.
We are the hollow men We are the stuffed men Leaning together Headpiece filled with straw. Alas! Our dried voices, when We whisper together Are quiet and meaningless
As wind in dry grass Or rats' feet over broken glass In our dry cellar Shape without form, shade without colour, Paralysed force, gesture without motion; Those who have crossed With direct eyes, to death's other Kingdom Remember us-if at all-not as lost Violent souls, but only As the hollow men The stuffed men.