Tennessee/LSU

[jimpiano]

The LSU/tennessee game seemed to end on a confusing play with the Tigers failing to get into the end zone, trailing by 4, as time expired.
In the bedlam that ensued a LSU player took off his helmet and threw it to the ground.
As we all now know the game did not end because the replay official ruled Tennessee had 13 men on the field before the snap.
When the down was replayed LSU scored to win.

As you might expect the internet talk argues the LSU player should have been penalized for the thrown helmet.

Common sense says the player should not be penalized since he behaved as if the game was over.

But what is the actual official explanation?

It is not a reviewable play?