What action should they have taken to deal with the person uploading it? Known that they were going to and gone round to sort them out? Why did the person upload it from the WhatsApp group to the public Internet?
It's that person that got them all in the toilet together. It was all of their responsibility to keep it among their little insular hate filled group, and they couldn't even achieve that. One can only hope we all descend into maddening threats of violence against these "juveniles".