A few weeks later, I was talking to an old colleague and they revealed that the story that came from stakeholders was that the accounting team found the error, and I left in disgrace (despite that not being my department?).

So if you find an embarrassing mistake and you do not control the narrative, you have to proceed very carefully.

so they made me not tell anyone I was leaving, and the letter was edited to make it less obvious how much of a better opportunity the new job was.