Has the AA driver caused more damage?

Hi all!

So im driving along when my car loses power and is low on revs, struggling to accelerate to 40mph in 4th. I pull over when i can and as i try to reverse into a space, the car cuts out. I try to restart the engine and no joy. I call the AA man...

The guy turns up, starts the car and it starts but revs are sitting low and it doesnt sound right. He thinks its an exhaust blockage so he bashes the exhaust with a hammer a few times and drives up and down the road. When he gets back he messes about with the engine for a bit and then drives it up and down the road again. It doesnt sound or perform any better.

When he gets back, he starts messing with the engine again and the car cuts out. He tries starting it so many times that he floods the engine. I then get towed to the garage.

The garage have now told me my cam belt has snapped and its destroyed my engine and needs a complete rebuild which will cost me £3500!

Did the AA driver cause more damage by driving it around? It started and drove when he turned up with just a loss of power. Should he have checked for any issues with the cam belt?

Thanks in advance!

Shane.

PS: I might switch to RAC!