Where did this rule change?
NFL Rulebook
Rule 7. Ball in Play, Dead Ball, Scrimmage
Section 2 - Dead Ball
Article 1. Dead Ball Declared
(o) when an official sounds the whistle erroneously while the ball is still in play, the ball becomes dead immediately.
(2) If the ball is a loose ball resulting from a fumble, backward pass, or illegal forward pass, the team last in possession may elect to put the ball in play at the spot where possession was lost or to replay the down.
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From what I saw, the whistle blew, and this rule should apply. How do you see it differently?
The rulebook clearly states the Ball is Dead as soon as the whistle blew.
And if so they replay the down.
So the post whistle pick up by the RB is moot. This is straight out of the rulebook.
Show me where it says they can overturn it after a whistle?
The search for whistle come up 20 times not one addresses your issue.
Also,
Section 4 - Non-Reviewable Plays
The following aspects of plays are not reviewable:
1. Whether an erroneous whistle sounded;
Ball Dead Immediately
Official sounding whistle 7-2-1(o), 7-2-2
So all this did he pick it up or not is moot. The whistle blew, the play was dead,
Instead of awarding two points it should have been a do-over. If in fact it was a backward pass.