The manager writing in for advice sounds like an awful person.

https://www.askamanager.org/ is an excellent site from which to learn the mistakes of others. I wish I'd read something like it twenty years ago!

Avoid the in-the-moment pressure of dealing with these types of absurd situations by reading about them before one of them happens to you, because it will, eventually. Remember -- "forewarned is forearmed".

Stay safe out there!