Fl Sunpass-License plate cover hide view?

[PDACPA]

Wife has the FL sunpass which is a little device that attaches to the windshield and collects the toll as you go through (when it reaches $10 on the device it recharges with the amount you set and charges your credit card). Saves having to slow down as much and dig for quarters.

Evidently it did not work (they claim placement on the windshield, yet I have installed exactly as the diagram says...so now their answer is the thin sunstrip of tint) and I get a picture in the mail of the rear of the Sporttrac with her license plate telling a toll violation.

Call the number, hey guys I have a sunpass. The system cant charge me but they waive the violation (of which there was no violation) this time.

Has anyone used one of those covers that obscures the view of the license plate from different angles. It would obliviate the incorrect violation notices that I just wasted 45 min on hold trying to get fixed and even though their system cannot just charge me the 75 cents like the violation letter says.