Well, nothing like a little heresy in the morning to brace you.  I'll go ahead and say that the presences in the vault are actually the legitimate Imperial governor and a squad of storm troopers, after the governor went to hide in the treasury the instant the attack started instead of broadcasting the defense codes.  It saved his life, considering he was only a few seconds ahead of the bomb that was supposed to kill him if he was doing his duty, but now the bastard is mighty<em>inconvenient</em>to be alive.  (since his presence means that Commodore Aquiarre acted illegally in promoting Cortez to governor, as that can only be done if the existing governor and the entire line of succession are already dead.  The governor appointed no heir, so it fell to the highest ranking military authority to pick the next Imperial Commander)