Accident advice

Hi all,

Any advise is greatly appreciated.

My wife was driving down a single road following the car in front a couple of days ago.

They came to a truck that was blocking the road (no hazards or driver present). the car in front went on the grass verge and passed. My wife then followed and when she got 3/4 of the way pas heard a bang...... one of the side panels on the truck had lifted in the wind and hit the back door and wing.

The driver then appeared and looked over and said it was just a couple of scratches and would polish out and gave her his name, reg and company name.

I arrived home from work today and lets say its not a couple of scratches.

What i ask is where to go, do i get in contact with my insurance? I have called the company who's truck it was and they gave me an email address to forward details across to.

Also who is likely at fault as I'm puzzled is it my wives own fault for going on the grass to pass, etc.

Thanks for any advise!

Regards
Matt