commercial site responsibility when pitching

Hi folks,

I am unsure of right location for this, but I am pitched on a commercial site.Today a van arrived to take the pitch next to me. The warden led the caravan with a tractor to the pitch where  he left the tractor parked in the roadway. He was guiding the caravan and car nose first onto the pitch.He told the driver to swing out wide and he would guide him in.He told the driver to come forward and suddenly the van a large twin axled van hit the tractor and  damaged the back  wing leaving damage to the awning trim and  side panel.  My question   is:   whose fault? The driver or his guide  onto the pitch?  Any advice please?