I informed my new insurance regarding 2 incidents even though they were none faults that are on my insurance and my proof of ncb form. One wasn't even anything to do with me a friend borrowed my transit and crashed into someone (his insurance) and the other was a big stonechip off an uncovered lorry and my policy went up.
You definatly need to report this to the police as its classed as an rta but regards the insurance I'd get money for the job ASAP or threaten insurance or you'll loose out.