The 14 VOR/DME approach is a lot less precise (it uses the VOR at the beginning of runway 19) than the 01 or 19 ILS. Even though it looks fairly straight in the Jepp it does not line you up precisely with the centre line like an ILS does. Minima is 600' and 3.2km vis versus 220'+PEC and 0.8km vis on the ILS. RW 14 at 1760m is only half the length of the main runway and probably getting a bit tight for a 737, especially when wet and carrying an extra 5 knots or so due turbulance.
Captain probably did not fancy seeing the runway at the last second whilst high ,slightly fast and not quite lined up and then having to land on a short wet runway. Too may things starting to add up here. He probably didn't think it was worth trying a second approach as things wouldn't improve greatly in 10 minutes due to the extent of the weather ,not just talking about an isolated CB overhead the field that night.Operations manuals normally limit the number of approaches that can be made before the pilot diverts (2-3)
Captain diverted and landed safely ,pax inconvenienced and fed up but the whole thing will soon be forgotten about.