Differential Unit problems of the 2011 Subaru Outback

My husband and I were driving from maryland to new york city late at night. All of a sudden, we heard a grinding noise and within 30 minutes our car completely broke down. No warning lights ever came on in the car indicating there was a serious issue. We had just gotten off the verrazano bridge. Had the car stopped on the bridge, we could have been seriously injured, if not killed. We came to find out that it was a full transmission failure. The Subaru dealer in new york indicated that there was no transmission fluid left in the front differential, but they could not find any signs of a leak. The valve body was repaired in September 2017 and at that time it was covered under Subaru's extended cvt warranty. At the time of that repair work, the Subaru service center who did the work confirmed that they had added some transmission fluid to the car. We contacted Subaru of America to see if they would help us with the cost of a new transmission, since the extended warranty had only just expired on July 31, 2018 (our car broke down on August 28) and because we had already had transmission work done less than a year ago. Subaru of american very rudely informed us that they have "zero financial obligation to us" and would not be helping us with the cost of repairs ($7000 to repair). We are beside ourselves with how this happened to our car. How can we have a full transmission failure less than a year after transmission work was done on the car and have no warning lights come on in the car indicating there was an issue? how did all of the transmission fluid leak out of our car without us knowing, and how is it that Subaru is unable to find the cause of the leak? and what kind of company does not stand by and help a customer with an issue that they clearly knew was occurring (hence extended the cvt warranty to begin with)? Subaru should have issued a recall on this vehicle.