Transmission Failure problems of the 1997 Mazda Millenia

I had problems going to a Mazda dealer (val strough Mazda, oakland, CA)in getting the transmission diagnosed. They first said it was the selector whcih cost $300 plus , then after changing it said it was the valve body and would cost $1200plus but were only 90% sure. If it wasnt I would have to pay an additional $3000 plus for a new transmission. They refunded only the cost of the part approx $100 but still charged me for labor that was unecessary. I decided to take it to a transmission shop who immediatley told me it was a mechanical problem with interior damage to the gears. It cost me $2500 to have a rebuilt transmission installed. Mazda should have been able to figure it out rather than trying to run up a bill which still would have resulted in a new transmission of course after paying $1500 plus dollars to figure out the problem. I also find it upsetting that a transmission would fail after only 68k miles. My mechanic (georges auto, san leandro ,CA) and the transmission shop (dons transmissions, san leandro CA) have seen many of these vehicles recently with similar and less mileage having need of the same repair. . They call it a very common problem one was reported within 2 days of mine another just 3 weeks later. As recently as this week I spoke with my mechanic and he's seen 3 more. There has to be something wrong with these transmissions. I was informed by dons transmission thatthere was a recall on the Mazda 626 transmission but I cannot find any record,the 626 uses the same transmission as the Millenia.