Bad service & lack of knowledge from staff

I went to the garage with my sister with her new Kia Rio, as inexperienced when it comes to vehicles. we wanted the guy to check out tyre pressure due to long distance. the guy came to us saying there was water coming from an engine. we opened the bonnet there was nothing but he insisted on opening the radiator cap and advised us the water was from the engine. he opened the cap and told us the water was green in the car and he had to empty the radiator water and refill with new water. the car has less than 31000 kms. one guy came and assisted the guy, they told him he shouldn't have removed the water from the radiator cause the water which he saw was from airconditioner cause it was running. the guy said eh will refill the water and told us it will be R87.00. on his return he told us R87.00 is per litre and we had to buy 6 litres to refill the radiator. this was an inconvenience as we had no cash and had to ask people to assist us. can this be investigated and educate your staff as this is bad service and we need our money as we feel ****** unwilling. now I don't know whether the car will give us problem from here. you can view the footage at your garage, we passed there on Sunday afternoon