Yes, but what do you do with those people. There is a similar situation going on in Chicago with the police union. Chicago did not enter negations with the union when they imposed a vaccine mandate. The deadline for vaccination has come and gone. A third of the entire police force has refused to provide proof of vaccination. Roughly 3,500 officers may be vaccinated or maybe not but aren't uploading proof either way.
As someone who has been a vocal supporter of vaccine mandates, what would you do if you were the mayor of Chicago? The police are already short staffed because they can't find enough people to apply. Murders and crime rates in Chicago are skyrocketing. Sheriffs in neighboring counties have gone on record saying they are refusing to send any of their officers to help in Chicago. Ron DeSantis in Florida has told the police union in Chicago that he will pay an immediate $5,000 bonus to any Chicago PD officer who relocates to Florida to become a police officer there. If the Chicago officers are fired or suspended without pay, likely a large number would take DeSantis up on the offer and be permanently gone.
So far, the Chicago mayor has blinked. They've suspended about 2 dozen of the most vocal officers but the remaining 3,500 are still there on the force. If you were the mayor with your convictions on the goodness of vaccine mandates, would you immediately fire 1/3rd of the police, knowing that people you represent will die as the crime statistics spike up, businesses will leave, and you will likely be blamed for all of it? Is that a price you are willing to pay to unilaterally impose a vaccine mandate on a unionized workforce?