Denis has said he doesnt do extended cuts and once a scenes cut its gone as far as he is concerned.
Speaking of cut scenes, I found another deleted scene in the Art and Soul of Dune book.
They filmed the scene of Duncan arriving on to Arrakis. It sounds awesome.
The Duncan Drop - Art and Soul of Dune page 128 & 130 - Tanya Lapointe
"The sequence began as Duncan looks down at Arrakis from his spacecraft. Pushing himself off the edge of the hatch, he plummets head down toward the planet, allowing the audience to discover Arrakis from his point of view. Duncan drops faster and faster toward the surface in a controlled fall alongside a rock face. As he approaches the ground, he activates his suspender belt and lands softly on a rocky elevation.
We filmed this scene with Jason in two locations. In Budapest and the Jordanian desert."
There are pictures from the scene in the book.