Car Stall problems of the 2019 Hyundai Elantra

My 17 year old son was driving the car to practice. It began to knock and smoke. It stalled in the middle of the road. We had the car towed home. A mechanic looked at it the next day and said that the engine was dead. A rod was thrown. The oil drum had other things leaked into it like antifreeze. I called Hyundai, because it is under warranty. (only 34,000 miles on it). At that time they informed me of the recall. It is an engine recall where the exact thing happens. It sat at the dealership for a week and a half before they even would look at it. Then they refuse to fix the recall. They submitted a "prior auth" for warranty repair. We had to submit oil change info (which we did). After 5 weeks they told us via text message that Hyundai denied to cover warranty due to neglect. They are blaming us when there is an engine recall on this car!?!?! they won't even speak about the recall, they are rude and told us to go to the bbb and get an attorney. I have attached our oil change receipts that we sent them. Please help!.