If you were driving a car then you had insurance, right? Then that's who you need to refer this to.
I am really baffled why three years went by before you heard back.
But that could be because you did not have an attorney for them to work with and they had trouble finding you.
I hate to say this, but I have been the person badly injured before by another driver. I went through years of arguments and my case never went to court. But I know how insurance companies work.
The insurance company still has to prove they tried to collect. If it wasn't your fault you may want to take that to a judge for some kind of mercy. If that is possible.
What the police officer writes is extremely important in a case. So, you may end up arguing your own side as a last resort.
Also, see if a law student in a university might want to take your case. Otherwise I don't know what to tell you.