Best to use a different protocol and avoid whatsapp.
I like the fact that WhatsApp's lawyers required the guy to preserve any digital evidence so they can use it to screw the guy later .. Yeah, let me help you screw me
Legal notices frequently tell you not to delete/shred/burn/"lose" potential evidence so that you can't later say you had no idea you were supposed to keep that stuff around. And if you did delete stuff they can try nailing you for spoliation
What happened to not being forced to incriminate yourself?