Okay, that's cool.
My interp of the play is that he took a very bad shot!
However, nowhere else in 4-43 is the word "fumble" used yet we still allow a player to retrieve one without calling traveling. How is it different?
I think the possible difference in the case play is that the player "allowed" the ball to fall to the floor. It's no different than lifting the pivot before starting a dribble.
Anyway, food for thought. I think the rulebook could be clearer on fumbles, airborne players, contact on the ball by the defender and traveling.