Now what if Q is saying the paintings were of children being abused or killed in empty swimming pools or baths. Each painting has different tile, these could be the actual locations where the artists was abused (though I do not know yet if she was abused alone or in a group). Maybe he wants us to understand that these private estates with empty indoor pools may be used in the same way. So the paintings were not from Biltmore activities- but similar activities may have happened there.