Vault 24. It was a Vault. A vault with a cloning machine in it. Besides that, it was a perfectly normal control Vault. Unfortunately, as normal as it might seem, it was still populated with people. And people which are enclosed for some 150 years in a giant tin can, well, that does a thing or two.
Today, the Vault has 900 residents, of which 200 are the kin of the forcedly cloned during the reign of the previous two Overseers. Considering that at one point, there were over 550 cloned per day, creatures ranging from radroaches to unfortunate Wastelanders that decided that Vault 24 is a harbour of safety .
It was not, and few remained the same. Most of the cloning attempts backfired in horrifying ways - radroaches that had human eyes, humans with radroach legs, etc. So do the terminals claim. All of those abominations have been mercifully killed... except for the John Jenkins clones, as they remain a reminder towards future inhabitants about what cloning can do.
That policy was started by the first Overseer since the doors have opened, one man called John Jenkins, with a supposed Biology degree. As far as the information Amber had on him, that expanded as far as to make statements how the humanity should be purified and that the best way to do so would be to clone away "the bad genes", as he called them, from randomly kidnapped Wastelanders. His lunacy went on even further, as he decided that all the critters of the Sunshine Wasteland will bow down to him, and that they must be cloned so that his "legion" can grow on.
To top it off, he decided to clone himself so that there are lil' Overseers everywhere. Some of them still live on, a harrowing reminder of the past.
An interesting anomaly was noticed, however. If you clone a radroach, a part of it's genes is stuck inside the cloning machine. This means that it should be "flushed", as it's called, regularly. Well, the good ol' Overseer didn't do that. This was also the source of terrifying abominations.
And so, one night, tired of the tyranny and plain out insanity of the Overseer, they knocked him out, pushed him into the cloning machines, which recently cloned yet another affront to nature, a mole rat cloned with recent two-legged radroach coming out, and clicked the button.
Several minutes later, something unholy walked out of there. A mole rat.. that was squeaking human words! Initially, the conspirators felt terrified, but then they felt pity. They felt that it would be merciful to die, but then again, did the Overseer ever give mercy?
This is where Amber's information goes. To this day, it's unknown - was John Jenkins let into the Wastes, where some Waster would end it's miserable life? Was he spared of a life as a sentient rat, and simply shot by one of the rebels? Or, did it manage to run away, and even now is roaming the vast Vault?
That, nobody knows, as the conspirators never mentioned the fate of John Jenkin's fate.