Just recently i read a theory that suggested the whole story line has just been a dream, upon reading this (and being a hardcore fan since CoDWaW and a huge fan of the Original 4 Characters) I thought i would put a theory up on here, this one is based from one i put up on youtube a while back.
Introduction...
So the base idea of this theory is that the ending cutscene is a look at whats its like to be the demonic announcer, so this in the cutscene is what it looks like from the view of the aether. As you can see a prop from near enough every zombies map his here, this is also how the person in control is decided (Orange, Red, Blue, ect)
Richtofen & Samantha
Once a person enters the aether they are automatically turned back to a child to preserve their integral conscience and to preserve their body's, also I`m going to say that with the power of the aether once someone enters they are "spread out over the timeline" meaning when richtofen enters the aether he is spread around over the space time continuum and able to see himself in past locations fighting zombies while his conscience is in the aether.
This theory is still a work in progress if you like this please show some love and if you disagree tell me why so you can help me refine this into a solid theory. Remember this is my opinion based of fact in the game, that still doesn't mean its the truth, thanks for reading!!