Air Bag Not Deploy problems of the 2012 Infiniti G37

I brought in my 2012 for maintenance at an Infiniti service dealer. I received a "new" battery as I was told the battery needed replacement soon. Come to find out, the "new" battery was actually a faulty component and my car would not start. I brought it in for diagnostics and they said nothing was wrong. I told them that it must be the battery since I never had that issue before. The battery issue continued and I would have to jump my car off. The day I had to bring it back to Infiniti, I had to jump off the car and right after I did, the airbag light began flashing and codes indicated a faulty diagnosis sensor unit for the airbag. They then did their diagnostics again and determined that the battery itself was the problem in the car-starting issue, yet the Infiniti bag light continued to blink. The dealer said the cost would be $1600 to replace the sensor/control unit. The airbag has never been deployed and I never had issues until the battery replacement with a faulty battery and thus creating the need to jump start the vehicle. The light came on right after a jump start. I never saw the light before that.

Car battery drained while car was unoccupied (in a garage) for two weeks. After jumping car operated as normal except for airbag light. Infiniti dealer informed me that the airbag diagnostic unit had failed and airbags would not deploy until a $1500 repair was done. Dealer noted that the unit likely failed when the battery was at low power or when jumping (jumped car exactly according to owner's manual).

The airbag light is blinking. I took the car to Infiniti and I'm told that the there is a failure code b1018 stored due to internal failure of occupant airbag detection sensor. They are charging $6,653 to replace this part. $348 is labor and the remainder is the part cost. The car has 47,800 miles and is out of warranty by 3 months. Infiniti USA told me that the air bag would not deploy on the passenger side and that I should replace it immediately as it is a safety hazard for passengers which are mainly my children. Due to the fact that this part is priced so far out of reach for most normal consumers, I asked Infiniti USA for some consideration as this is my only car. They declined any type of assistance in replacing the part. In other words, its dangerous enough for me to pay almost $7000 to replace it but not dangerous enough for them to help fix it. I was told at the dealership that they are seeing this sensor issue more and more on cars 3-4 years old and that they are not making them like this anymore.