One thing I do not understand about each map taking place in a different universe

So with the two ciphers between Richtofen and Maxis that were solved in ZNS we can pretty much say that each of the maps in BO3 take place in different universes, correct? Der Eisendrache is in a different universe than The Giant/Zetsubou/Shadows, and vice versa for the other maps. I can certainly agree with this and don't have much of an issue with doing so if it wasn't for one thing. What are the odds that the same stuff exists in each universe we go to?

Let's look at some ciphers. On The Giant we have ciphers that relate us to DE (mountain searched for frozen one) and ZNS (Cell below the waves). On DE we have ciphers relating to ZNS (Division 9 Island Facility, Ancient Beasts). On ZNS we have ciphers relating to DLC 3 (Brother in the city, Gersh, V cipher, dragon cipher). So what i'm to understand is that all these ciphers exist in the universes we're in and correlate to things that are happening in a completely different universe?

Okay so maybe it's just pieces of paper or whatever bleeding into other universes. I could buy that. Maybe those ciphers exists elsewhere in time and space and somehow ended up where our characters are. However ZNS takes it a step farther. If this idea is correct that would mean that ZNS and Stalingrad (DLC 3) are gonna be in different universes. In ZNS we have a room where there are dragon eggs, dragon blueprints, and blueprints for a device to control dragons. We can only assume we will be seeing these dragons in DLC 3. Makes sense from the information we're given in ciphers and quotes and whatnot. So now i'm to believe that these dragons exist in both Zetsubou's universe AND in Stalingrad's universe? The same dragons? The same ones that Division Nine were working on to help the same group fight the same war?

If i'm understanding this idea of different universes correctly it means that in all four of these universes (TG, DE, ZNS, and DLC 3) world war 2 is going on, the same sides are against each other, Group 935/Division 9/Ascension Group all exist with the same exact members, the same stalemate is occurring on the western front, and division nine teams up with the russians to create the same dragons to break that stalemate. It just seems like it all lines up too perfectly. I guess the only explanation to this is that Maxis found all the right universes that really do line up perfectly. Just seems like a poor way to tell a story in my opinion.