Who committed the crime in Cris et Frisson?

The answer is actually cyrille and sonia. Turns out they both are having an affair, and they want the money to leave the company and go to france. Sonia does the virus infection from adding it onto a software of hers, which takes the money. Cyrille and sonia open an account named M. Valence, and gets the money from there. Cyrille hides the evidence from taking away the 5 missing videos