[quote]As far as the retinal scans, the ghost says "or something kept them preserved". It's not to say they are the eyes of the one who actually awoke him.[/quote] That's the point, tho. To have had access to Rasputin's bunker, they would've had to have been military or scientific staff. If they survived the collapse, they'd be wandering around with accounts and evidence of what happened during the collapse, almost certainly trying to restructure Earth's defence within the structure that they were used to. No records like that exist. Along with Ghost's line, it's pretty obvious the retina scan was completed with bits of a preserved corpse. You're not going to find preserved corpses lying around a warzone :p Ergo, it's not unreasonable to consider Maya having held onto important parts of her physical heritage when opting to Exo herself.