Long story short me and my car got hit by a bus and the guy took off. I’m fine, but the car is damaged. I need to pay for most of the repairs because of insurance issues. I can afford it, but it’s still expensive. I’m starting to have self-doubt, this is my first car accident 😭 
In my country non-emergency police requests are, generally initiated by submitting a written request. That said traffic problems generally are handled on scene by the road police, and they usually want to photo and catalogue everything, so leaving might have been a problem in that regard.
However, you can still probably open a case and hope CCTV or some dashcam caught the situation.
E: This may or may not solve your insurance issues too. I have to imagine the reason they are denying the repair bill is due to the accident not being properly filed with the police?