Infiniti USA did not warranty item that bad during powertrain warranty period Nationwide

I have an 2011 Infiniti QX56 that I bought on 1/1/2015 with 56,000 miles on it.   Had so many issues with the selling dealer they offered to buy it back but I had already sold my wifes car at the time so I just kept it.  The vehicle had a torque convertor shudder and I was told by the selling dealer that it was out of warrnty and nothing else could be done.

My mistake for just trusting the selling dealer.  But I put it in writting that I was not happy with them selling the car with this issue and this is what prompted them to offer the buy back.   But come to 2016, I find out it should of been under warranty and send the email to Infiniti dealer and Infiniti USA and corporate stated they would pay half of the repair even though they read my email that is all they were offering.

I told them this was not good enough that they should pay for teh full repair being I had documentation I complained about it while it was in warranty.  They contineue to disagree and say they will only pay half.  We will see.