The driver of the vehicle received a PCN with contravention 47J stopped on a restricted bus stop or stand (approved device)
Therefore the driver is the RK, so why refer to 'the driver' as if a separate entity(overtones of private parking charge notice jargon here)?
If you are the RK but not the driver then the driver shouldn't have the PCN, it's for the RK to action. They could make reps to the effect that the vehicle was hired or similar (after all it is a PHV/taxi) if applicable and therefore relieve themselves of liability completely, or accept procedural liability and make reps on other grounds.
We've seen a couple of threads jeopardised recently for want of knowing who's who and unauthorised persons attempting to make reps.