I'd say using a phone provided by your boss to set up a whats ap group to then dirade your boss is a sackable offence. Not least in that it shows a complete lack of respect and how on earth can a boss that knows his employees have been privatley rail roading him have any respect in those around him and continue to trust them. Off with their heads dont do the crime if you cant do the time. Of course its all conjecture.
This, I've seen many people get sacked for using company provided forms of media or email facilities to slag off the company or their higher ups. It happens every day all over the world I should imagine. MIG seems to think this is akin to watergate.
Move along, nothing to see here except someone with an agenda.