It would seem like you'd just need to learn to play their "game".
A group of guys get together, including the CNC programmer, and buy a bunch of 80% lowers. Each guy owns a percentage of every gun, including the programmer.
All the work is done and each person sells their ownership in all but one lower for 1 cent. The programmer, who may or may not actually want to own one, can sells his portion for a bit more.
How would that be illegal?
If they are manufacturing firearms with the intent of selling off their ownership of said firearms, I would think they would need an FFL07 to be legal.