With the Top picture as is, I see another stress crack to the left side.
It could have had a 2nd strike to the "0" in the date, and the metal was weak and it took a hit from another coin and shattered part of that "0".
Since you can see the base of the coin through the "0" pretty clearly, its potentially another 0/0 that is found when the coin received damage. Thats my guess.