have you contacted Elite customer service and started and issue with them? I would.
The key question you have to answer is can you live with the defect or not. If not, then ask for a FULL refund. I would (in parallel) see if Elite can investigate a repair. A repair is a longshot. Especially inlight of what was reported here that Elite said they would give a refund for a defective IR sensor! They're not repairing anything it would seem.
I feel your pain. you did your research, bought the best, and its defective and you can't get another one. There is another possibility, now that you're arrived at your budget (and please share how much you paid), what about the 80inch 844? it's full array so uniformity should be good. but alas the black levels won't be as good. oh and it's a bit more money than you probably sent.