Neighbour drove into scaffold. Now claiming damages.

We had to erect scaffolding for emergency roof repairs to the flats I live in. Our neighbours are an office, so the scaffold was in the form of a drive under gantry so as not to block access to their car park. The footprint on their side of the fence was eight sole plates (150mm square) rising to poles. The gantry was 4m high.

The office general manager has now contacted me to say that one of their staff punctured a tyre while reversing as "they could not see". I struggle to see how they could hit the footplates with a tyre without the car body/bumpers hitting the scaffold poles. I've asked for clarification.

Nevertheless, should they show that the scaffold was at fault, who would be liable? Us, the scaffold company, or the driver who managed to hit a 10m high gantry?