Because they were guilty of trying to look after too many kids, which while maybe against some local statute or organisation rule, is probably not a police matter. I think the article title could have made this sound a little worse than it actually was.
The police seem to think they need a secret room because they want a place to hide the kids if they get inspected. But you're right, it might also be a rape dungeon.
Then ask why his care facility needs a secret room.
That would depend on how much work they put into it. If the "hidden staircase" was simply a sheet of drywall dragged in front of a prexisting basement door, then they could just be horrifyingly irresponsible cheapskates.
Or they're child traffickers; hopefully we'll get more on this story.
They cared too much? Building a false room seems a bit over the line.
Well it depends what the fine is for having too many kids. maybe i'm imagining something different to everyone else but I have a room in my house where If I push a bookcase against the door it becomes a secret room also. If they went to more trouble than that then I might be worried.
Why was no one charged? Why does a daycare need a secret room?