The pool area has the most haunted worse experiences of feeling frightened. I believe it is exactly the pool showing those kids in Podesta's art.
https://www.candidslice.com/haunted-biltmore-my-firsthand-paranormal-tour/
The tour led along a narrow passage to the side of the pool, which though empty, was incredibly deep. As we passed by, I saw the black figure of a woman glide under the water and rise from the pool, on the side where we stood. There wasn’t a ladder there, though she ascended the side of the pool as if there was. Around her was a shadowy grey blur, and she was very upset, crying, and trembling. I felt that she died there, and she stopped at the end of the line of guests, and spoke to me. Her mouth moved, though I couldn’t hear her. Keep in mind, I was fifteen years old. I was so frightened that I closed my eyes until the group moved on.
Others have noted similar experiences in the pool, including feeling overwhelmed by the spirit of someone who drowned there, hearing voices, and empathic past life recall.