Is there some evidence indicating that Dow was aware of the tampering, and diverted these specific shoes? That strikes me as a less plausible explanation than the one I’ve suggested.
But that doesn’t change the fact that stuff which is going to be shredded always goes through a screening process first and those specific shoes-with-trackers-in-them were never going to reach the grinders and were never going to end up in paths/pavings, even if they did get to Dow. Because I mean, obviously.