Have you ever checked-in code that caused problems for the company?

I have taken down an entire major website multiple times with both code and operations.

It's harder to do for a product dev and it's harder to do in a mature infrastructure, but if you work in infra and you haven't caused a nearly complete outage of the system you work on within a year or two, I would question if you were making any real changes to it.

If you get blamed for the outage as an engineer your management is bad. Outages are a result of managements decisions and priorities, and generally not a result of engineer negligence. Blaming an engineer is a way for management to neglect their responsibility. Extreme Ownership is a great book that talks about this.

Like, checked in secret keys to a public repo?

Or bad-mouthed a co-worker? Or used degrading descriptions?

Or added code which, given a directory with a space, caused the wrong files/directories to removed?

Or checked in code in violation of copyright or patent law?

Or included comments which, when dug up by the opposing party's forensic expert, aided in making discovery requests your company would rather not have answered?

No, never. None of these.

a civilian dot-mil contractor in California said over beers that he was asked to place some code in some repo, with a misleading comment and untrue name.. he did it, so he says.. It was a brag. He is the president of his company, they were paid very well for many years. He has a custom built home in the expensive hills area here, where he sits in bed reading news every day now, due to poor health and painkiller use.