Vehicle dashboard damaged

I took my car in for a service on 04 Feb 2015 and when I got it back it had a sticky residue on the passenger side dashboard.<br> <br> I brought it back and told them to please remove it and when the guys from Auto Armour had a closer look at it, the dashboard was actually melted/rubberised on section that lines the top air vent.<br> <br> Mark has vehemently denied any responsibility for what happened and after much back and forth communication, I gave up and I am now using my insurance to claim for a damaged car. Mark denies that their workshop was at fault and when I look at the work carried out I see that they replaced a cabin air filter DIRECTLY underneath where the dashboard was damaged.