motorcycle accident

my son was in a motorcycle accident. A car came out to his line of traffic and stopped, blocking is lane. My son dumped his bike rather than hit the kids car. My son totaled his bike and he and his girlfriend suffered major road rash where they went to the hospital and spent our an hour being scrubbed. It left them in a lot of pain. There was no dent on the car because he decided to lay down the bike rather than hit the car and risk fatal damage. The kid asked him not to call the cops in fear he would get in trouble. So my son didn't. Now the family of the kid is claiming it wasn't the kids fault and there is no proof because there is no damage on his car. My sons roommate called them though and they admitted to him what happened. But now they are refusing to take blame. should the kids ins. co. be responsible for pain and suffering, cost of bike and hosp. bills?