9-9-1 EXCEPTION in New '18,19 Rules Book

[TopicalTropical]

I'm still a wee bit confused so please correct me. After looking at the powerpoint-

1. - A1 in his frontcourt makes pass, defense knocks it back like in the video. A2 in backcourt catches the ball in air or on a bounce. Violation? No in both cases

2. Same as 1 but this time, B1 knocks ball off A1's leg. Ball then goes into backcourt. Violation once A2 touches

3. A1 in frontcourt with ball, A2 also in frontcourt. A1 makes pass, B2 deflects ball to backcourt. Can A2 go get the ball?

4. Say a press like situation, A1 has ball, A2 is in the backcourt, then frontcourt, then back again. A1 makes the deflected pass off B1, I assume it is not a violation here and A2 can get ball.