Nonsense: charges are based on declared MTOW , not actual T/O weight .
The issue seems to be ( if I understood the article correctly) between FR which declared all its aircraft to have a MTOW of 66,9 Tons , and the manufacturer data which says MTOW 75 Tons.
What is on the actual Irish registry certificates would be interesting to know.
If the Irish allowed 66.9 and someone can prove flights were systematically made well above that figure, the problems for FR and Irish CAA will be far more complex than some money fines about route/landing charges......