My thinking on this is the disk brakes and pads come under the warranty of the car so it would be the dealer to sort out if indeed there is anything wrong with the brakes and I find that hard to believe if the car is under 3 years old, more so as its the rear disks as they ware at a slower rate than the front one unless your driving with the handbrake not fully released, something else I find hard to believe.
From the days before disability and I paid for my own repairs every visit to KwikFit to fix a puncture would return remarks along the line of “your shock absorbers are on the way out” or “brake pads are low” and so on so those sorts of remarks are pre-programmed into the operative from their bosses to boost earnings though he overlooked there not allowed to work on Motability cars other than it’s tyres.
Going back 15 years my son was a manager at a KF branch for a couple of years so I know exactly what they get up to and can’t imagine anything has changed in 15 years.