I am not sure if the CFI is aware or not, I guess he has heard 'their' side of it.
I did ask to speak with the owner (Director) of the flying school, I was told he was too busy. I told the desk that I will be leaving the school if the director would not give me 5 minutes sometime that day, I was told to leave my number and he will call me sometime for an appointment! They allowed me to walk out knowing I would not come back so I guess I know where I stand.
They can shove their school were the sun don't shine if I do not get a call with a sincere appology (at least).
I must admit, I have been warned about their penny pinching antics for at least 3 years. I have been stung for incorrect bills (in their favour) many times. Having additional landings added onto my bill weeks later, attempting to charge me twice for membership and even once claiming I hadn't paid for a full hours flight (they did apologise for the last one when I proved them wrong, again!)