I'm not sure any of the ATC aids are relevent to this accident, unless I've missed some major part of the argument. The crew failed to fly the internally monitored approach correctly.
Whilst the accident may not have happened if there had been a working and used PAR (or equivalent), it still seems as though the approach would have had to be aborted due to the weather. Therefore I'm not sure the ATC aids are relevent even to the recommendations of the Accident Report, never mind the causes.
I still think we should be focusing on why they failed to fly the selected approach correctly. I've given you my best guess, based on what others have kindly contributed to the debate. I'm open to further thoughts and info on the theme of the incorrectly flown approach.