Did he make the input after the hard landing in a desperate attempt to just get her on the ground?
That is probably the most likely explanation. (Also the wrong thing to do as you probably know...)
What is curious is after the initial bounce, the apparent rotation to a G/A attitude, the appearance of an initial go-around (the proper choice), the airplane seems to be climbing away from the runway, and then the sudden pitch over.
Did the crew simply lose control of the airplane?
It appears they had it made had they selected TOGA gone around.