You can certainly talk to a lawyer for much less than $10k. The lawyer will either (a) tell you to forget about it (b) tell you that it's not worth using a lawyer, but that you might be able to pursue it in small claims court or (c) send a letter, which is probably all this would take, if he has any standing at all.

If the other side lawyers up faster and better they're also paying more, and with a $100 letter it might be easy to convince them that lawyers typically aren't worth it for amounts under $25k.

For what it's worth, your intentions were clear to anyone who's actually read your post. Good luck, you did the right thing.

And again, what does that (blowing up the database) have to do with a referral bonus?

He also told the world that Miso doesn't have great engineering practices. Deleting a few thousand rows is easy if you forget a "from" clause in your sql statement. Would you consider working at Miso if you knew about their poor moral standards and bad engineering practices?

I feel like more people should be publicly shaming companies so that companies realize they can't pull shit without consequences. I bet you there's a whole list of companies that fire people right before they're eligible for pension benefits, and there's little employees can do.

Docking wages for employee mistakes unless (and perhaps even if) wilfully negligent is /highly illegal/ in every state in the US, and will have the Labor Board all over your company and slapping you hard with fines and punishment.