The third Newton's law declares what each reaction of forces should be symmetrical.
where: F - reaction forces of objects
The consequence of this is law of momentum conservation.
where: F - reaction forces of objects, m - mass of objects, v - velocity of objects, dt - time trame of action, P - momentums of objects.
This consequence should be used for case where objects induce same identical motions and this does not cover the case where objects induce different type of motions. In experiment 2 thin cylinders induce different type of motions and this simple consequence should not cover this objects repulcing action. Therefore, for correct explanation of experiment 2 needs to use prime third Newton's law and identify all reaction forces by this law. The consequence law of momentum conservation where objects have symmetrical behavior should not be used for this objects repulsing case.
Another interesting point is a symmetrical angular momentum. During repulsing action just one object has an angular momentum. Base on law of momentum conservation the isolated system should have the symmetrical angular momentum. However no any other physical objects have it. Base on modern classical mechanic, this symmetrical angular momentum is exist potentially if calculated distance between center mass of isolated system and center of mass of objects. But here both objects induce together this symmetrical angular momentum from theirs translational momentums cancel and their linear kinetic energies conversion to rotational kinetic energy. But where is another energy which came form symmetrical repulsing action for angular momentums when symmetrical forces repulse objects?
Or, if repulse two objects symmetrically away from theirs center of mass then both objects will have same linear momentums and same angular momentums.
However, another unpaired potential asymmetrical angular momentum is exist between center of mass of isolated system and objects center of mass during their linear momentum cancel. This could be explained by same sentence. The consequence law of momentum conservation where objects have symmetrical behavior should not be used for this objects repulsing case.