Not only do we have no idea who he really is, neither does he!
LOL
Actually I think there's a lot of truth in what you said. He thinks he's everybody - a citizen of the world - and ends up being nobody.
When a person lies long enough, sometimes they begin to believe the lies themself. The thing about telling the truth is that you never have to remember what the last or former lie was. This tripup seems very telling. There have been a lot of things hidden, covered up, and just plain erased about his past. Maybe some of those skeletons are starting to come out.