This is a common sense/ logic ruling.
The question is really, if one creature knows the space an enemy occupies, does every allied creature?
If you allow your PCs to tell other PCs the exact square of an enemy between turns then it only seems fair enemies can do the same. If you only allow players to talk on their turn and share the result of their Perception checks at that time, it makes sense that monsters are equally restricted.
Assuming they have a shared language and are intelligent enough to coordinate or use tactics.
I'm not even sure you need a language. I used to be able to point out squirrels to my dog, he would literally see me point and follow what I was pointing at.
But even knowing exactly where someone is may not reveal them, there are too many factors.