There was one sure thing that the Penntons didn't consider, and it is that Katherine was tipsy on the night she got assaulted. Moreover, knowing her violent personality, it wouldn't be wrong to consider that she might have intentionally offended someone who sought to teach her a lesson the hard way.
The camera in the private room also showed that the four girls were seated in their rooms when the situation occurred, judging from the time given by Kate in her narration.
Before the four girls were to be transferred from the police cells, the lawyer found a solution to the problem and had it presented before a judge. At the end of the day, the judge tasked the police to find the real culprit, as they were also ordered to release the four girls on bail.
