Without proof of the accident- good luck.
When I got hit most recently I called the cops and made sure they ticketed the guy that way I had proof he was at fault.
I gave him the options of either paying it himself or letting insurance take care of it. His insurance company called me the next day and cut me a check a week later.
I also got $250 for saying that I was not hurt and not planning to sue for my scratches and bruises. Since most states don't have any policy for rental car bike equivallents, that's how I spent it.