Seat Broken problems of the 2006 Chevrolet Trailblazer

2006 chevy Trailblazer spun out on snow while my daughter was driving. It went towards the left then immediately jerked around to the right and continued to gain speed as it launched us off the roadway and into a group of trees. The brake pedal wouldn't budge, the steering wheel continued to turn in circles not controlling the tires at all. The backseat broke apart before impact and was throwing my teenage son around in the back. The front seats broke loose as well and slammed both driver and passenger into the dash during impact. The seatbelts did not engage to lock into place like they are supposed to and despite full frontal damage and a SUV deemed totalled/destroyed by my insurance company, not a single airbag deployed or attempted to deploy. We were all trapped inside the vehicle down an embankment and all sustained injuries in the crash including cuts, bruises, whiplash, and my daughter had a concussion. My daughter had a vp shunt placed in her brain last year and could've easily died in this crash due to her injuries. Something needs to be done about these airbags and seatbelts not working!!.