This is straight from the NFHS.org web page on 2007-2008 Basketball interpretations.
"SITUATION 10: A1, in the team's frontcourt, passes to A2, also in the team's frontcourt. B1 deflects the ball toward Team A's backcourt. The ball bounces only in Team A's frontcourt before crossing the division line. While the ball is still in the air over Team A's backcourt, but never having touched in Team A's backcourt, A2 gains possession of the ball while standing in Team A's backcourt. RULING: Backcourt violation on Team A. Team A was still in team control and caused the ball to have backcourt status. Had A2 permitted the ball to bounce in the backcourt after having been deflected by B1, there would have been no backcourt violation. (4-4-1; 4-4-3; 9-9-1)"
http://www.nfhs.org/web/2007/10/2007...s_interpr.aspx
It's the same as question 76 in the IAABO refresher test. This ruling says A2 has caused the violation. So based on the IAABO answer, they disagree with NFHS.