Was the union aware that there was a transfer happening?
Was the union aware that there was an employee that was skipped over on the bid sheet?
Was the union not supposed to enforce the contract with regards to transfers?
Was defending the seniority skipped driver not the obligation of the union?
Was the union aware that there was a contract violation for all 11 months?
You say the union is partially to blame, but I'm not seeing it.
And with you saying you don't have all the details, I'm not sure you should be saying it.
The union relies on the members to report contract violations. They don't just magically know what goes on inside the buildings.