I think the most likely person is Desmond from Point Lookout. The dude is on the hunt for remnants from the Old World, and it's very likely that one of those remnants he's after is living in the Big Empty. Hell, even if that's not the case, wouldn't they want to address Desmond's relationship (or lack thereof) to Mr. House? I mean, Desmond came from a group of intellectuals who knew the Great War was coming, and basically made their bets on how to survive it. Sounds VERY similar to Mr. House's backround story.
Other than that, Desmond seems to have the means to actually make it to the Mojave. The way he talked in Point Lookout seemed to imply the dude was used to traveling.
I can't think of anyone else who would both be able to make the trip to the Mojave AND whose backround story seems relevant to any person or place in the Mojave.