Bad customer service and lying

It's sad to say that this branch of supa quick does half a job almost cost me and my family our lives and then still wanna tell us we are lying, we went to balance our wheels of the bakkie, before a long road trip, and as soon as we hit passed 100km/h my husband felt that they did not balance the tyers at all (this after paying for it), on our way back from the road trip the tyer blew out next to the road on a busy highway ( obviously due to the extra vibrations that were paced on the tyers from not balancing properly) we took the bakkie back to them and the blew out tyer and they started giving us attitude and telling us that we are wrong and that the tyer burst is not there fault ( all the other tyers also showing signs of close to blow out) and argument later the guy that did the balancing admitted that he didn't balance the tyers and still they are telling us its not there fault, it now cost us to replace all 4 tyers and they put us in danger. Greenacers supa quick bad service and cant take responsibility for there faults.