Well, maybe Burke is a skilled hacker that knows how to hack the social media of the DIKs and get information from their computer via online, with a virus or something... But it´s easier to think that he´s just blackmailing one of the DIKs. It would be really easy for him.still don't understand why and how he has access to the DIK's PC I mean, if someone gave him why ? oes he balackmailed the DIK ? Or if he procured it by himself how did he do ? and still the same question : WHY ?
For me, Jamie is the one. He says he can´t sleep well. Why the writer tell us that? He´s implying the character has regrets. And the obvious reason is because he´s the "traitor". But there is a problem with this: how Jamie would get the video of the MC with Cathy? He can use the computer, but it´s supposed that he don´t have the password of the folder where the video is... Maybe he just copied the folder and gave it to Burke, and Burke is the one that hacked the password
Why Burke would try to harm Cathy's reputation? Because she´s his ex-lover and now Jade´s best friend. Make sense that he wants Cathy to resign.