Amarok wiring issue

I purchased a VW Amarok in 2015, the vehicle now has 118000km on the clock. After breaking down VW told me that there was a wiring harness issue caused by water getting into the harness via the tail light causing the Megtronix unit to blow. They sent me a bill for R197000.00 to repair it. After kicking up a stink the offered to pay a portion reducing the bill to R70000,00. They won't budge any further saying the vehicle is out of warranty! Where in the world do you pay a repair bill of R70000.00 for a vehicle that is only 2,5 years old because some water got into your tail light? Insanity... !!! I will never buy a VW again! Bullies!