The installation of the cameras being detected all depends on if there was an installation of the lights simultaneously, or if it was done separately, and even in such a case it's dependent upon the both DIKs paying attention, and them knowing what to look for if they did, and neither of those are true as evidenced by their behavior and complete lack of technical knowledge.
And I just noticed that Quinn actually has a light identical to that in the closet in her room, makes me thonk
. What if Quinn is also being spied upon, what if Vinny installed a camera in her room as well, what if it's actually Quinn behind the cameras, in which case she'd be videoing everyone who's buying from her in her room.