Bad service, worse than it was before

A terrible experience. My cambelt had to be replaced and it took 3 days for it to get it fixed and it was done until late at night. When it was diagnosed they picked up that the oil belt had to be replaced, the water pump and the flanged. But now one of my cats pipes in the engine is leaking water. So for me it wasn’t a good experience. Also I was quoted for the diesel while I am using petrol. When I brought it up they said i was going to be reimbursed but before that could happen I was told that the part costed more than my initial part and they will cover the cost from their pocket which I didn’t receive any quotes or breakdown