Your math fails relax because you clearly missed one or two of the pearls. I'll try and dig up the relevant one later for you.
Missiles have their antennae on the rear aspect of the missiles. For the controlling ship to communicate it needs a clear LoS to that aspect, and vice versa. For attack missiles they do this in sequence each moving to a position in the wave where it can clear it's after aspect for a moment, (they maneuver enough on the way in to create issues from maneuvering alone).
So your 3d falls apart because if any CM's have another CM behind them they get no comm data and don't work. You probably could use the MDM approach in theory, but based on various bits of info my understanding is that CM's require much more control link management over their whole flight. And certainly before the control links cut they have to spread out and assume a 2D formation so they're all locked up before the CM's lose them to control loop lag.
And no, i don't think the CM's can see each other, they only have sensors on the nose, even if those are 180 degree arc their fellow CM's will be out of sight. They can't respond to each other maneuvers and one of the pearls mentions that MDM's don't intercommunicate except for Apollo control missiles which is a special exception. Given MDM's run pre-programmed attack profiles, that's not an issue. CM's have to respond to unknown maneuvers by their targets and so need to clearance to maneuver safely.
Anyway i'll see if i can find the pearls now.