I'm more inclined to think that guy is actually the main character from Fallout 2.
Spoiler Afterall, he mentions learning a spell from a caverat about how to make others show their true form, "That Gun" from Fallout and Fallout 2 can be found and purchased in the Mojave (meaning it's previous owner sold it out there most likely), and the Highwayman is broken down just south of Novac.
No bark noonan is the chosen one? That's a pretty crazy theory, but it's somewhat plausible now that you mention it.
But yeah, there's a survivor to Vault 11, no one knows exactly who.
Also, the reason they killed themselves is because they found out that the whole time they would not have actually been killed by the mainframe, that refusing to sacrifice actually freed them.
so were is the password to get into the overseers computer?
It's down the hall, you have to find the assembly hall, on the podium there's a speech, picking it up gives you the password.