Result 3: QB fumbles snap, picks ball up & laterals in desperation to o2, who attempts pass
For the QB to lateral the ball, he had to have control of it, and if the o2 received the lateral it is implied that is was a legal backwards pass. And, any player is allowed to attempt a forward pass, so the pass would be legal. This would be scored simply as one passing attempt by the offensive tackle.
Result 6: While faking handoff, QB bumps into another back, he retains possession but loses 4 yds
Again, this will be an official scorer’s judgment call. If he believes that the fake handoff was on a play designed to be a pass, then the QB is charged with one sack for -4 yards. If, however, the scorer believes the QB was attempting a rush, the QB would be given one rushing attempt for -4 yards.
Result 9: Ball carrier fumbles in backfield, ball bounces away, he recovers it while running towards own goal, is tackled for 20 yd loss
Since the ball carrier had possession, fumbled and recovered his own fumble, he is charged with one rushing attempt for -20 yards.