I can't find the definition of "dropping" in Rule 2.
If it's an intentional act, the best you can go with is "throwing" it and so you must take into consideration the pass rules.
The act of "throwing" is not defined either, but common sense (and Websters) define it as propelling the ball in some matter, even if that's with a flick of the finger. Unless you rule that the ball is in motion solely and completely because of gravity and not Newton's third law, then you have propulsion, which is throwing, which is a pass.
I have never heard of (or ruled) that a player intentionally fumbled a ball. If the act was intentional, then in my mind he threw it. And if that's the case, then I rule on whether it was forward or backward by rule.
Besides, this is obviously a planned play so therefore it can be assumed A10 wanted to ball to go to a specific place, i.e. throwing it even with the ever-so-slightest of force.
All of my rambling aside, in simplest terms call this lame play incomplete and you've saved the coach a 5-yard penalty even if he deserved it by making us have to officiate this play.
By the way if you don't rule this a pass or in the vicinity of the snapper and you let it go, start thinking about 4th down/try fumble rules as a fumble is all you have left as for ball status.
I am so bored at work and it's only January.