As I recall from the Troy Brown blocked punt lateral-return against the Steelers in 2002 (AFCG), it does not matter at all where the ball lands. Read the rule book. The ball must be thrown backwards or directly to the side. Troy Brown was running forward fast. He flipped the ball backward. But the ball was caught beyond where he let it go.
Now, you ask, how can a ball thrown backwards travel forward? If you're moving fast enough, it can. Try throwing your cash filled wallet backward out your moving car window (and let me know when you're about to do it). I will be standing a ways up the road from where you throw it.