Yeah the wording in the picture makes it sound like cats aren't supposed to be behind the door, because they can't get out. The implication being that I should open the door to let them out.
If you need a toilet, go in and to the left…
HOWEVER, keep the doors closed because cats are not allowed in. They are not able to get out and have [passed] here.
Just kidding with the last part. They just get sad, hungry and poop on the floor.