That's something that's been puzzling me, pretty much from the beginning.Why dihidrino. Why not quadrino. After all, the bond must not represent the "classical" QM bond.
Once you start down, why not go even deeper.
Mills proposes a revolution in physics, which would up-end most of chemistry too. Yet he seems unbelievably conservative when it comes to exploring the implications! Only one (two?) fractional quantum states (why not a googolplex of them?) Only one element with such states; only textbook chemical bonds;
only atoms (by not protons?); ...