They forgot it was Motability and were trying to rip you off. I’d be making a complaint to VOSA none of that looks like a failure to me. I’ve got tyres on the car now that have marks/cuts from gravel like that, sure if you shove a screwdriver in and pry it apart you can see cords but pretty sure an MOT doesn’t include doing that.
Also how thorough an inspection are they doing to find that, ice never known in 30 years an moths like an mot tester to spot tiny things like that they don’t have the time.
I think this dealer just got caught trying to rip people off
Tyre sealant expired, ffs