Hoffa,
Such scenarios are practiced in the sim and the outcome and subsquent failures will depend on the imagination of the trainer driving the sim.
I don't know if you saw some of the photos of the Qantas 747 that had an oxygen bottle explode ripping through wiring looms. Capt Pit Bulls, rundown is very good but the list of ECAM drills and subsequent failures will really depend on the manner in which the door leaves the airframe.
Does it happen? Not seen it, I think a United(??) 747 lost a fwd cargo door and it was messy, but it did land. But passengers did fall out! Not with each other I hasten to add.
Q
Standing by for the Boeing boys telling how they wouldn't survived in an Airbus.........