It is an extremely bad idea to bring coworkers into the scene at the time of firing and it's an even worse idea[1] to bring unnecessary people into the decision about firing - especially if they effectively have no voice in the decision.
You probably won't notice most of your coworkers leaving - but there are a few you'd likely feel deeply and people do occasionally need to move on. Go grab a coffee with them after the fact (or during their two weeks notice if that applies) and get your empathy in - but before someone is formally let go it will just hurt moral to spread that news too widely.
Especially in a small company, sometimes it’s best to cut your losses quickly and toss the rotten apple over the cliff rather than go out of your way to stomp on it and deal with rotten apple stuck on the bottom of your shoe.
Definitely not a 10x, just a scam artist.
Did you only fire him because you found out he worked other jobs or because he didn't do enough work?
(He was also not doing an amazing job - he required constant supervision without which he wouldn’t produce any meaningful output, presumably because he had 2 other managers he was trying to please at the same time)
It’s not so much about whether he was a good coder. More that I can’t trust someone with production database access if I discover 6 months in that he has 2 other full time jobs.