The rules for Hiding state:
Until you are discovered or you stop hiding, that check's total is contested by the Wisdom (Perception) check of any creature that actively searches for signs of your presence.
When you hide, there's a chance someone will notice you even if they aren't searching.
Generally 5e tries to stick to plain English and tries to match real life where possible.
It seems to me that the rules are written in a way that says detecting a Hidden creature must be done on a per-creature basis. It isn't clear to me that if one creature detects a Hiding enemy with Passive Perception or the Search action, all other creatures automatically detect it too.
Obviously in real life even if one person detects something, they need to at least communicate that to others. And even then that can often be not enough for the second person to detect the thing.