Hyundai Kloof Constantia is selling shady cars

My wife bought a vehicle from the Hyundai Constantia Kloof in 2017 September. The vehicle has been fine and she has barely done 10 000KM in the 2 yrs she has had the vehicle and suddenly this week the gears stopped engaging and got stuck on reverse. when trying to dislodge the reverse gear something in the gearbox "popped" and transmission oil dripped underneath the vehicle. We called insurance who came and collected the vehicle for assessment and it was found that some previous shady work was done on the vehicle Gearbox which The Constantia Kloof Dealer had never advised my wife on and now the vehicle has fallen out of warranty on this basis so they will not fix and replace the transmission. The cost is R60 000. The sales guy there Stanley who sold the vehicle to my wife has just been brushing it off and not attending to the matter with urgency. I spoke to the dealership manager Rudi and I am awaiting to hear what Hyundai intends to do as we need the vehicle fixed. My wife uses that car to get to work.