Its common for the dealership to do a video of the health check and highlight any faults. Likewise kwikfit they have to send pix into motability of tyre tread depth before approving replacement tyres.
It is just motability making them jump through hoops.
If you do not take the car back, its the mechanic and dealership that gets it screwed and not motability.
I would go back, because its the little guy that gets it in the neck, but that is entirely up to you.