Follow up...
Similar incident a long time ago (early 1980's). Insurers refused to entertain a claim against their client, as he had not filled in an accident report form, so as far as they were concerned 'no accident' - despite Police involvement and successful Police prosecution for 'failing to stop after an accident; failing to report accident; and driving without due care and attention = then 3 Endorsements, plus hefty fine..... The idiot even got his girlfriend's father to attend court to say he was at their house on the night of the incident, but I had witness and police did a very thorough investigation, matching paint, and investigating his 'newly repaired front end etc, enough to nail him (he ran into my rear end, reversed away, and drove off!)
I only had 3rd Party insurance then, as a young lad, so no option of going through my insurance. Advice was to get car repaired and claim back cost via Small Claims Court.......but I didn't have the money to pay out for the repairs in advance (or even the confidence in 'the system' to get my money back), so did a repair job myself (with help of my dad , bless him), and the ar*e who did the damage got away with it (apart from the Police stuff). I often wished that I had followed it through the Small Claims Court, and it is much easier to that nowadays, and knuckled the idiot, but I don't suggest that you follow that route, however tempting it might be, as it can easily get out of hand.
I really thought times and systems had moved on and progressed, but you hear of far too many of these types of story - hence my comments about a complete overhaul of insurance - long overdue.
It sounds like a no win situation to me, but your insurers should really be taking on his insurers; or you go the small claims route?
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