Yeah, I saw.....
So, I claim I was 60% right. (THat's what I get for going for a conclusion without ever having looked at the calculation.)
But I'll amend my comment in this way: I would think that the two stable Lagrange points are small islands of dynamic stability embedded in a larger island of dynamic instability. So, I still doubt there will be much space flotsam there....
I don't know. I'm an ex-JPLer but a programmer not a rocket scientist. I recall reading a science fiction story that used that idea as a plot twist. The space ship in the story was accidentally sent through a Lagrange point and the ship suddenly started getting pummeled with junk until they changed course to avoid it. The moral being what you don't know can kill you.
My guess is that there would be garbage there, the same as Jupiter captured asteroids as moons, but I'm neither a rocket scientist nor a mathematician.