One question that has been raised is whether the crew were making a third attempt to land at a strongly fog-bound airport because their fuel level was low enough as to give them little other option. The initial Wikipedia report indicates that it had been in the air for about 2 hours at that point. Now, depending on model, the Fairchild Swearingen Metroliner (also according to Wikipedia) may have a range as little as 1,065 km, and a cruising speed of 515 km/h.
That indicates a duration of about two hours.
If so, there might not have been sufficient fuel to divert somewhere with no fog.
I make the distance from Belfast to Cork to be about 350 km, so flight time should be about 40 minutes. Even with departure time (taxiing and waiting for a runway) tacked on, they should have been nowhere near two hours.
