I haven't seen any discussion about how well this crew must have done in landing promptly on the approach end of the runway. If I recall correctly, Southwest is using HUDs in their aircraft. It would seem logical that this helped reduce the touchdown dispersion and contributed to the success of the landing.
Once they determined to land on that particular strip, they were fortunate that the runway was not 500 feet shorter, but then again, if it was, they may have recognized their mistake.
If I had not flown into a particular airport at night before, I think I would have absolutely confirmed the proper airport using appropriate navigation. There are too many of those darn things out there to just assume you have the right one in focus. This has to be mental complacency. Just the thing that SOPs are designed to prevent.
Fate is the hunter, waiting for such omissions to strike. You have all sorts of bells and whistles to make things safer, but if you fail to use them properly, you are back in that type of aviation that Ernest Gann wrote about where it all rides on the skill and determination of the guys flying. This time the hunter was denied its prey but the opportunity was there.