Preliminary begs more questions. Mast was 66m, terrain elevation at the tower was 370m, so they were at 435m/1400' ASL, crossing a ridge with a 100' to spare at night in reduced visibility at what, 130 knots???
Sounds like they departed the Massarelos hospital pad, needed fuel, and tried for Baltar which is enroute to Macedo. Only IFR recovery possible was Porto airport - nowhere else has an instrument approach. Once away from the coast the MOCA on a nearby airway is 7000' and off airways quadrant altitudes 8100.
Starting to sound a little like BlackRock. Some questionable SOP for a very routine local flight by an operator that thinks of itself in the big leagues. Regulations cannot anticipate every possible condition, there has to be an operational oversight and "attitude" that is impressed on the flight crew by the management of the AOC.
Bottom screenshot is Google Earth view of the tower in the flight direction at the 1400' eye elevation. Porto airport is north of Massarelos about 10 miles.