Tire Sidewall problems of the 2014 Chevrolet Silverado 1500

Hello, I noticed sidewall bulging on all 4 of my cooper discoverer a/t 275/55r20. After googling I saw that a recall exists (NHTSA campaign nr:21t002000) then I called and sent all my dot to cooper and they said my tires are the wall-mart special version which is not included in this recall. So I tried wall-mart and they are not helping either (no recall exists is always their answer. . . ) my 4 tires are the exact size and produced in the week listet in the recall 21t002000 and show the exact same issues (big bulges in sidewall which are filled with air) just the fact that it is a discoverer a/t tire not a discoverer a/t3 4s makes cooper tell me my tires are not in the recall. I believe there are more faulty tires out there and you should look into this since 4 out of 4 tires I have are bad. I am happy to bring my car to you guys to analyse.

The contact owns a 2006 diamond c 12chs (na) trailer equipped with vail sport st lh99 tires, size: st205/75d15. The contact noticed a fracture on the sidewall of the rear driver side tire. The tire was not diagnosed or replaced. The tires were replacement tires. The manufacturer was not made aware of the failure. The VIN was not available. The approximate tire failure mileage was 2,000.