M365: One department sharing folders with several departments

Our accounting staff generate excel files with each Excel charge for each employee that has a company credit card so we can reconcile our charges with the appropriate budget.

Someone foolish set them up with an AMEX team and showed them how to make different folders for each cardholder, even though it means everyone can see each others’ card spending. Their thought process was who has time in our busy environment to read through their peer’s card charges.

Well, that person who set that up wasn’t counting on the Microsoft Feed growing into what it is now, throwing everyone’s AMEX report in front of everyone else.

That person has since changed their mind and decided to post in here asking about a better path forward when one department is responsible for several others. Do I… I mean does he just remove everyone from the Team and use share links for the folders for each department? Is there an easy way to audit the permissions for when staff leave or simply to double check the correct people have the correct permissions?

Also, this method is used elsewhere as well, so cleaning up this concept is valuable even outside of card reconciliation. I’d love to make the Microsoft Feed more valuable, and if I could simply hide certain sites from the feed that would be fine as well.