Is it possible that the WestJet crew saw that they could go just a little lower with an early descent below path to 500 feet before D2.0 and lost track of the altitude before breaking out so low? Does the B-738 give an audio callout at minimums on path that they were expecting but may not have got due to the setup in the box? Obviously, altitude needs to be closely monitored whether the automatic callouts work or not.
I would really like to know how they got themselves to almost sea level short of the runway so I can avoid the trap they fell into next time I’m in that position.
Giving the benefit of the doubt and assuming that they didn’t just bust minima and get woken up by the 100R call, what could have led to this incident? Visual at MDA but going slightly under then a confusing picture? Following an inappropriately programmed flight director in a visual segment? There’s no extended approach lighting so you’ve got to be able to (continuously) see the runway and/or slope guidance in order to continue.
What was so convincing that it almost put them in the sea following it?