Left with a bent bike?

On June 7 this year a lorry backed into my bike then carried on reversing another six feet, pushing it into a parked car. The bike was left stuck in the grill of the car.

The insurance company got the bike assessed and say it is only minor damage like plastics etc. Having spoken to engineers I was advised to ask to get bike laser checked to see if the frame and other things were in line.

When I asked for this to be done they refused and said it was down to me to do this if I thought it was out of line. So now I have been in dispute with them since June and it looks like I will end up with a bike that is not safe to ride and unable to sell. What would you do?