I am not making the case that the NFL has responded correctly to either Rice or Hardy. But both happened before the revised policy was issued. But the Rice case had video of the punch.
Second, if there are photographs, I have not seen them. Thought I made that plain. A link would be helpful. Did she require treatment for injuries as well?
Lastly, the police were called, she did give a statement and she testified at the trial by judge. But there are signs that there may be inconsistencies between the two accounts and she is not willing to help. This doesn't mean that Hardy is suddenly wonderful, but there is not enough that the prosecutors feel they can win a new trial with a jury. The best the NFL could have done under the old policy was something was 2 games. They got four plus the exempt list season. For a bad policy to produce anything close to that is a muted win.
Its possible even that won't stand in court. But no player or team employee can see that as a victory for the abuser and a free hand.