My cleaning lady would occasionally bring their daughter to help out. I see no reason to behave overly hostile and tell the cleaning lady her daughter isn’t allowed. This only occurred after years of the cleaning lady working and trust being built, is something is missing the cleaning lasy is always the first assumption. I never had a secret camera in a bedroom and wouldn’t spy on the cleaning lady with a camera like a freak. The OP sounds like they have a few screws loose for having secret spy cameras in the bedroom.

If the story is even true their excuse that it can be accessed by the balcony doesn’t make sense, I see no logical for th reason to be in the bedroom rather than the balcony where it can also act as a deterrent.