Flap extention etc
The passenger notifying crew of lack of flap extention was very much in his right to have done so and the crew member should have notified the crew as a standard procedure.
I remember very well a flight from Heathrow to Goteborg in a Trident some time after one bought the farm there because the flightcrew had not selected slats etc etc...................I read the preliminary investigation findings in Aviation Week on board the aircraft. Needless to say I made damned sure I saw the slats and flaps selected before take-off.