Wrong. There is more than one way to do things right and what this individual did is one of them. Had this person showed up for or allowed progression into a verbal and/or physical altercation then yes, totally unprofessional, illegal, etc. Showing up to meet and have a respectful yet corrective conversation? At worst this individual possibly violated company rules by not reporting the incident a.k.a. not throwing the scheduler under the bus. Instead, this person actually did the scheduler a favor and even sacrificed some of their own time to do it. Quite generous and definitely not bad judgement, a mismanagement of time, or bad problem solving. It is actually the exact opposite. This individual could have easily reported the guy, thereby jeopardizing his job and ruining his employment file, but didn't. That was not only professional it was also very selfless and benevolent. Don't think even I would have done that and I consider myself a pretty nice person. The scheduler probably learned or remembered to treat people better, something which would have been a roll of the dice had a replacement been hired. Possibly helped improve conditions a little for everybody.

Restorative approaches have their place and should be taken in such places. Just dropping the full weight of the hammer on somebody is not always best. Doing nothing and just "eating the $h!t sandwich" is what is truly extremely bad judgement, bad time management and bad problem solving. Professional aviation would be better if more pilots would stop doing nothing.