Very very similar to the Kenyan Airlines crash. The autopilot on the 737NG cannot be engaged while force is being exerted on the control column.
Possible scenario: PF calls for A/P, PNF reaches over nd presses a/p engage button, p/f sees this to be a confirmation that he's now on a/p whilst hand flying and without checking FMA (a/p has not engaged). PF lets go of the controls.
Pilots then get busy with something else and aren't monitoring the attitude UNTIL g forces alert them to the developing Unusual Attitude. It's then too late.
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"TOO LATE? Why?" Pilots looking up under increasing "g" and seeing an extreme attitude, find it hard to register what they are seeing and frequently roll the wrong way in their panic-stricken recovery attempt, consolidating their fate. Scenario happens more often than you hear about and only the fatalities make it to the front pages.
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SOLUTION?
As mentioned by me many times before, the killer in this recurrent accident scenario (Flash Airlines, KQ507 etc) is the A/P push button. If you replaced it with the old style paddle-switch, it would not solenoid engage under g while banked and would just flop back to central without that satisfying tactile click of fully-deflected engagement/retention. Your alert of a failure to engage would then not only be the switch not remaining latched forward (flops back to central upright), it would also be a flashing glareshield alert light just below your forward line-of-sight (not hidden away on the FMA amongst a bunch of other annunciators).
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Until Boeing fixes this it will continue to kill pax in their hundreds.