Sorry, thought I was in the HS forum. I have him with possession with his first foot in, which in HS is all it takes.
But watch the ball as he lands OB. It moves, meaning he wasn't able to hold it firmly throughout the recovery process; thus, no recovery, which makes it a free kick out of bounds, untouched by the receiving team. So, the result of the play is B's ball at the out of bounds spot. And, there is a foul for an illegal kick OB, and the 5-yd penalty may be enforced at the previous spot or added to the spot where the dead ball belongs to B (the latter being the most likely choice).
Absolutely not A's ball in any way.