ALL indications are that this was an instance of the most common (non airline) coastal instrument approach in SA (probably Africa).
Descend as low as you dare out to sea (using the gps), and then sneak back to the airfield under the fog (again using the gps).
Separate people from the problem. This is not a criticism of the pilots concerned, it is a criticism of all the pilots (probably several hundred) who knowingly descend below GRIDMORA over the sea to get into IMC airfields. It is a criticism of a system that seems to tolerate if not encourage cowboy behavior.
Hopefully CAA will start taking action......