This has nothing to do with visual acuity, it's all about the geometry which creates visual illusions. The outline of the shorter, narrower runway will be identical to the longer, wider runway at a particular point in the approach (the location of that point varying based on the actual dimensions involved). This is an important visual illusion to remember so that you can prevent confirmation bias from leading you down the path to a similar mistake.

The B747-400 doesn't have a Garmin 430, it has an integrated flight management system.

The FMS database doesn't include Jabara airport because the runway specs for Jabara airport do not support an airplane the size of of B747. The FMS told them exactly where they were, in Lat/Lon, but it had no idea that there was an airport there. The FIX page could have told them their bearing and distance to Mc Connell and would have been a good place to use to cross-check on the enroute chart for their location.