Clearly noble gentleman convicts! Perhaps these people think Wakefield Prison is like the prison in Paddington 2. All marmalade sarnies and Hugh Grant musicals.
Wakefield is known as Monster Mansion, Mark Bridger and Mick Philpott are in there along with Roy Whiting, and Sidney Cooke. Murderers and paedophiles. Would they be deserving of a high five if it had been them killing Watkins. What it Watkins had killed Roy Whiting, would that be good or bad?
I shed no tears for Watkins, but let's not pretend there is some sort of code of honour being played out here and these men were acting out of some of moral conviction. They're all dangerous men who will continue to be dangerous and have no ethics or values.