What do you expect?
If you pay for a certain plan, that's the plan you get. When you exceed it, your use is restricted. That's the way it works. It's called a "contract", you may have heard of them.
This is purely the fault of whoever is in charge of selecting the service plan, not Verizon ... with the caveat that yes, their customer service department could/should have made an immediate exception due to the emergency.
Note: I'm no fan of Verizon or any other telco ... and I have the utmost respect tor all the responders working the lines in California's fires (I live in Sonoma). But pu-lease, don't pass the buck, Bowden. Suck it up and admit you made an error in judgement over your department's data needs. Being a firefighter is not a get out of jail free card. What's next? Pay for 1,000 feet of hose and expect to receive 2,000 feet?