What is difficult about 800m and 600ft?
Nothing except that according Jeppessen the minima for the VOR/DME approach requires a visibility of
2.8 KM and the MDA(H) is 1125 (524') for runway 03 and 1200' (530') for runway 21. NDB approaches have similar minima.
If they use Jepps. minima then they would not be able to make the approach if the visibility was the 800m you estimated. They may of course have been other factors that we do not know about.