Just some food for thought here, have an MS in maths and was intrigued with the puzzle. I don't really understand a ton of the zombies lore or any of that shit, but for people that do maybe this can lead to something idek man.
The tesseract theory for the BO3 EE certainly does seem interesting, but honestly I'm not really sold on the K-cubes and n-cubes theory. Largely because of some information I may have connected with Bo4, but in short any sort of mapping from a hypercube would be incredibly arbitrary and if we were to even try to extrapolate information from data to project in 4d space it would just be a nightmare.
I think a more reasonable interpretation may be along the lines of $K_n$ for a complete graph on N vertices. In short, it's a graph of N points that are fully connected by edges to each other, where each vertex is connected to each other vertex by a single edge. If you wanna read more in depth, check here. The main things to highlight is connectivity of each of the nodes. When I originally saw KN-44, the first thing that comes to mind in this train of thought is a complete bipartite graph of (4,4). This is a graph for 4 vertices on each side, where each vertex connects to only each vertex on the other side, but not the same side. Wikipedia here if you want to look more in depth.
I'll elaborate on Bo4 first because I think the connection is more clear. Bo4 also has the KN-57, and this is one of the reasons I assume there is another easter egg hidden similar to the impossible Bo3 one hidden in Bo4. Keeping in mind this numbering theory we laid out earlier for bipartite graphs, we can construct K_n(5,7) which connects a group of 5 verts to a group of 7 in a complete manner. My main conjecture here is what if each of these vertices represented maps. In Bo4 there are 8 maps, and we can separate these maps into 7 maps and 5 (five as in the map Classified). I theorize there may be some objects, materials, or just anything linking each of the other maps with Classified somewhere in the map. From there, it could be objects within the Classified map that are from any of the other 7 maps and maybe even a wall buy location. I've genuinely never played the map or even Bo4 in general, but I assume there are people here that may know something about that and maybe be able to take it from here.
As for if this logic holds for Bo3 or how it does, my second conjecture is that it has to do with each of the crew maps (DE, Gorod, Zetsu, Giant) overlapping with Revelations. Allow me to digress.
Something of note to add in relation to the Bo3 part though is that entry regarding the KN-44 through the campaign terminal secret access shit. It references a KN-42A3 and KN-43A2. This is odd as usually A_k isn't used to reference values when it comes to graph theory like this, but it is commonly used in permutations and arrangements particularly with Lie Algebra or Lie Groups. A_3 would reference Special Linear Group 4 (also known as SL(4)) and A_2 would reference SL(3). SL(4) is a group containing 4×4 matrices with determinants of 1. Determinants are the combined products of all elements of the matrix into a singular number, which in this cause happens to be 1. One interpretation here could be once again when we combine all elements of the 4×4 matrix (4 maps) combine into 1 (Revelations). I reckon this further feeds the idea of the bipartite graph theory. A3 I imagine references some other set of 3 that combine into Revelations, but as for what those 3 things are escapes me.
Anyways I have no idea how helpful any of this shit is, or if I'm just too high to formulate a complete thought at 10am on a Thursday, but it felt somewhat reasonable so I'm posting this in hopes an actual Zombies expert can take it the next steps it needs to go.