Did they sell it to a debt collection firm? That could explain why when you called, they were fully aware and more than happy to take $24 (probably bought the debt $0.24). Once sold, it would be taken off the official system.
That said, yes, it's BS. I never authorized out of state companies to have access to my information via license plate.
Ran into an issue a few years back, traded in an RV out of state and forgot to grab the old license plate. When I realized, I called and the dealer agreed to remove and destroy it. I then got toll bills from Illinois, NY, Mass., & Florida.
I had proof, I wasn't in any of those states at the times in question but they wouldn't consider it. Finally had to get a police report. Then they wouldn't accept sending it via email. I had to pay postage to send it to them. Never did get confirmation back that they received it. For all I know it's still there but I'm not paying.