Mate, it's a simple matter. Do humans have nictating membranes on their eyes? No. Ipso facto, the muscles used to exclusively move said membranes are by definition useless. That would be like having the muscles required to move a third arm, without having a third arm. By the way, nictating membranes are those horizontal, transparent "eyelids" that some reptiles have. If you see a human with those, I'd run like hell.
So you're sure it doesn't have another function? This is like saying cardboard box is only for packing
Imo its too many different cogs too maintain different functions. Trust me, cybernetics organs is the future that we want. Wall-E future chair is the technological wonder that we need.