I'd consider replacing it with an external cooler. When I had a trans fail on a Mitsubishi Eclipse years ago the trans shop highly recommended installing an external cooler because of possible blockage in the factory radiator integral one. After the rebuild I drove the car another 6 months, and sold it to my brother who drove it for a year and after he sold it I saw it around the area still being driven many months after that.
Basically my rambling is saying, if it a brand new trans burned up that quickly then it sounds like a blockage problem. If it is not blockage then it would have to be electrical.