User blog comment:Argorrath/Treyarch releases a BO2 teaser video called "Origins" for DLC 4/@comment-58.107.17.15-20130808080321/@comment-1263839-20130808093210

Just remember that in the Zombies Canon, they weren't at Verruckt/NDU as they appear in-game.

But otherwise possibly, I thought it was just meant to symbolise the whole "every story has a beginning and an end" thing.