Inspection cost not covered by AON insurance.

My mum's vehicle was in an accident, a taxi hit the passenger side of the vehicle, subsequent to the accident the car drove perfectly fine. The auto-gearbox no longer selects any gears. We asked that the car's gearbox be inspected as we where certain it was related to the accident. The assessor had recommended that the vehicle be sent to Mayfair gearboxes. The assessor then authorized the repairer to proceed with the stripping for inspection. Before any work was done to the vehicle the I confirmed with the assessor that in the event it is found that the gearbox damage is not related to the accident that i will be able to take my vehicle away with no cost due by me.The report revealed that the damage was not accident related and the cost to repair was almost the value of the vehicle.I called the repair co. informing them that i will not be proceeding with the repair as it was unaffordable and a waste of time as i could sell the car \as is"after the body repair. It was then i was told i needed to pay the inspection cost of R3000 to release the vehicle. The assessor give them authorization and he received the report not me. AON refuses to cover cost for the inspection."""