Advice car insurance

We need advice, my son (22) was un a fight years ago with his best friend, and the friend went to the police the next day. He didn't end up pressing charges, and they are friends again, but the police continue the 'process' I guess and a couple of days ago I received an email from my car insurance that a explains that as my son has a conviction, the car insurance will go up to 850 dollars a month. We called a lawyer, and she told us we can fix the legal problem but is going to take some time. In the meantime what can we do with the insurance??? We don't live together, I was helping him with the car insurance, but I can't pay this, and when I tried to cancel it they told me they will not until I provide evidence of a new insurance. Both his and my car are own by the bank, and we live in a city without public transportation.