PilotWolf
If you know who this person is, and it seems that you do, shop them ASAP, you have a legal and moral responsibility to do so.
If they are deliberately ignoring instructions on the manouvering area, they are a severe risk not only to themselves, but many others.
There are several anonymous ways of doing it, but a confidential report to the aerodrome authority should suffice, and go someway to ensuring that this person never works airside again.
Bandit
I don't know where you work, but I can assure you that your situation is very rare throughout the UK.
It sounds like the airport authority are only paying lip service to what should be taken very seriously. Perhaps a submission to CHIRP would be in order.
If anyone thinks I am ranting or preaching, I've witnessed the first hand results of failure to comply with such procedures, it wasnt pretty and it took 23 hours to find all the pieces.