The NTTA is good to work with you. We have toll tags on all of our cars and we once had mix up with the 2 main toll tags getting switched by accident. Of course, the camera was reading the tolltag correctly but the car did not match the toll tag number. We got a bill in the mail for about $500 for the tolls plus fees and when we showed them what happened, they waived everything execpt the actual toll charges.
I think you should be ok, especially if you call them before they send a bill. Also, like a couple other responses.....they don't pursue you if you miss one or two, it is the people who routinely run the tolls they go after.
Good luck and rest a little easier I hope!
Susan