He told me that if they report damage to an aircraft which they have caused no action will be taken... However, if they damage the aircraft and don't tell anyone they will be dealt with severely.
Oh I like it. Sort of blackmail? 'You punish us and we won't ever report anything!' Clever. Obviously works. I wish that worked for other staff!
Are you serious about ground handling staff travelling on the flight deck? Why? What exactly will it achieve? All that is required is that you do your job properly and carefully. Examples like this incident will not be solved by towers sitting on flight decks. Just don't wreck the flight decks!