1998 Range Rover Brake pads replaced

I had brake pads replaced by an individual but after that I had some liquid leaking from the rear brakes on the passenger side which has caused erosion on the chrome wheel so I took it to a mechanic who told me that whoever worked on the brakes did not have the experience to work on a range and may have caused the liquid to leak. He told me that I had only front brakes and that the rear brakes were not working due to abs and he couldn't work on it because he doesn't specialise on brakes. What do you think is the problem and how can it be fixed.