Don't know how it works in detail in other countries but in the UK the aerodrome licensee has overall responsibility for making sure that drivers are competent although this is often delegated to vehicle operators or other third parties at large airports.
If a driver is not up to the job then a word with the airport ops people should get it sorted.
If it was unsafe or if not action is taken by the airport I would say it falls within the MOR scheme and should get reported.