The second guy obviously comes at Johnno first, you can see him try to have a swing while Johnno's wife is in between. Johnno then belts him one, which is probably why he hasn't complained as he has instigated that confrontation.
the first guy, the teacher, has lied to Johnno's wife about the video being a snapchat, and backed up his lie in this video. It's obviously not a snapchat as he still had it.
I don't condone violence or Johnno's actions, and he shouldn't have put himself in this position, but the two other guys in this incident have created the issue.
If they didn't video Johnno (and CCTV camera's in the kebab shop show that it was unneccessary as security camera's are there to capture this kind of behaviour) and then if they didn't lie to his wife and then if they didn't try and man handle her to get their phone back then the issue could have been avoided.
But Johnno should know better.