Tossing The Ball Into The Air ...
 

And he has five seconds to accomplish this. While a few things that he can do in the five seconds time interval would be illegal, like stepping across the boundary onto the court, or throwing the ball into a basket, I'm not sure that tossing the ball into the air to himself is one these possible violations if accomplished within the requisite five seconds.

Is the case still closed?

You are not quite understanding the case. He throws it to himself while having OOB status. There is no violation in this. It would be a violation if they threw the ball, stepped IB, and was the first to touch the ball.

Also, this is not 100% accurate. (it is legal to throw the ball to a player out of bounds. A violation? Yes, but still legal - rule 9-2 Art 2)



How about this one:

After made basket Team B, ball bounces near corner near official. A1, in a hurry and OOB, grabs ball and throws it to nearby IB teammate. The ball strikes the official on the arm and caroms back to A1 who is still OOB. A1 then passes to A2 who is IB. Legal?

This would depend on whether the official was inbounds or not. If the official was out of bounds, legal play. If he was inbounds, it is a throw-in violation, because it touched the court inbounds (an official is considered part of the floor), and went out of bounds without touching a player on the court.

Did the scenario say that he threw the ball to himself while out of bounds? If so, that would be a legal play, albeit one that might lead to a 5-second violation.

What I meant about legal was a play that would not be a violation or cause a violation. Only throwing the ball to a player who is inbounds, to another out of bounds player after a made basket, or to oneself without crossing the boundary line is legal, and only if no other rule is broken.

Words Matter ...
 

"To oneself without crossing the boundary"?

Crossing the (plane of the) boundary line, or crossing the boundary line and stepping inbounds?

Not the same. Words matter.

A player is inbounding the ball and a parent yells, "He's stepping on the boundary line". Officials often want to sound the whistle, stop the game, and say, "The player can step on the line, but not over the line onto the court".

Crossing the boundary line and stepping inbounds.