While an interesting hypothesis, I can confirm that north/south movement is nonexistent. As with the soda-can analogy, a constant wiggling of the leg would have very likely resulted in the material being slighly deformed. However, as can be see on the second photograph, the leg doesn’t appear to have any deformation.
Another interesting information bit is that the cut happened at a point of the leg that is inside of the switch housing. If wiggling would have occurred, I would expect the leg to be cut off where it meets the housing’s leg-opening, as it would be likely for that border to cut into the leg. But this is interestingly enough not the case.
It remains a mystery.