When the cow wheel pucks collide with another object (other pucks and the catching arm), the physics become crazy and they dart around abnormally. The easiest way to reproduce this is to hit a puck with the arm without catching it.
Attatched below is my recording of replicating the aforementioned bug:
The only noticable difference between the servers was the player count. US East 2 had around 20 people while US East 1 had over 50. There were also no other players playing the machine at the time.