The coolant system of my car is contaminated with transmission fluid - what can I do?

I own a 2012 Seat Exeo ST 2.0 TDi Auto. One morning I found a pool of transmission fluid and water on my drive. It was towed to a SEAT main dealer and they informed me that the coolant system is contaminated with transmission fluid. The two possible fixes are changing the gearbox and cooling system at a cost of £10k plus or changing the radiator, flushing out the system and topping up the gearbox at a cost of £1000. Can you advise me?
If the car engine has not been started then there's a reasonable chance that little or no coolant got into the transmission, so it's worth having the transmission fluid replaced by dialysis using a Liqui Moly ATF transfusion machine (member of The engine cooling system also needs to be flushed of transmission fluid and the radiator and heat exchanger replaced. Cross your fingers...
Answered by Honest John on

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