This problem is being misunderstood and mis-analyzed by everyone. Firing a worker under typical union labor agreements (which have been agreed to by management) is difficult and time-consuming. Management in this case quite clearly did not follow the rules since the workers were promptly fired to avoid bad PR. Thus it appears that the arbitrator probably came to the correct decision in terms of contract enforcement. Management was simply lazy and/or stupid and/or trying to trade off short term gains for long-term damage.
(continued in next post)