My daughter had a similar thing happen last year. If you are not at fault do not accept the 50/50, insurers use this to reduce their outlay by splitting it and and allows them to increase your insurance premium and you lose points. My daughter? After many months she was eventually found not to be at fault, she did need a trip to the hospital after the accident and had a minor back and neck injury but did not ever claim for that, this possibly helped why she won and the other driver to blame if you know what I mean.
Another with the wrong registration it is:-
PN15 GKJ not GN15 GKJ
Besides that it looks a scary scenario hope you and your daughter are not too worried. Go ahead and report it, who knows what the motive of this sicko had.
I just went to put this on here and you've done it already :)