Gross negligence

A friend went to the BP opposite the Cape Quarter. He asked them to put in power steering fluid, they started putting in brake fluid and luckily he was standing there to stop them, but some had gone in already. He then spoke to the manager there at the time and the manager told him not to worry he will sort it out, just leave the car here and they will sort everything out. They then sent his car to Ford to get fixed and said they would cover the costs no problem. The next day Ford calls him and says they received an email from BP saying they will not cover the cost of R2400 and he must pay if he wants his car back. After calling BP and trying to get hold of the manager that he spoke to speaking to a different manager he was told they will not take responsibility it is the petrol attendants word over his. Obviously he needs his car to get around and had to pay Ford himself. This is blatantly unfair in my eyes - why would any normal person tell a petrol attendant to put brake fluid in his power steering fluid????????? If this was me I would not have been standing there and watching and would have just driven off destroying my car completely. How is this not their fault????? It is unfair because BP is a huge company and surely they have insurance for such mishaps and in these Covid times every cent counts. Trying to go up against BP in court would cost a lot of money that he doesn't have but I am hoping by putting it out there, there might be some justice served somehow and to make us ladies aware to watch the petrol attendant we trust so much with checking the oil etc. I never do but will for sure from now on!!