Refund for vehicle repairs

On the 22nd March 2023 around 11 am, my girlfriend's car was contaminated at Shell garage Winchester columbine, the Attendant poured transmission oil (ATF) into the brake fluid oil, and the whole cars braking system was affected and the car couldn't brake anymore. We went to complain at the garage and the manager by the name of Muneef Absalom, is still "assisting" us it's been about a week now, and still, no help, all he needed to do is to check the camera and check if his attendant did contaminate or not and still today we are waiting. I was instructed by Muneef himself to send him all slips and bank statements to ensure that the transaction was 100 % done at his garage on Monday 27th March 23 I sent him everything including the card details that swiped, and he then told me after he got the information he needed he told me it will take him three days because he is busy with other things, three days later I still don't have feedback or update from shell Winchester. Muneef assured me that he will send me a full update on 29 March 2023 and here I am on the 30th still clueless because I am not a priority to shell Winchester. Muneef told me that even if the Attendant did contaminate that person is not a mechanic so we can't blame him, blame him for not knowing the products his company sells and that he uses every day to service shell customers. SHELL since Winchester Shell doesn't want to assist my girlfriend and me or rather take their own time to help us, what is an alternative solution for us? #Shellsouthafrica please help because no one else is.