HDR photographs from Colorado converted to 16 bit images to give a "zoned" PWL appearence. Will this work in PainterX to give a good result?

I like the properly done HDR images and would like to see it applied to a painting, if it'll work.

Will this fly or is it a crash and burn?

Among the characteristics of traditional "paintings" is they aren't supposed to look perfect in terms of detail and colors. That's what distinguishes them from photos.

While the HDR concept can be applied to any image, for something you intend to autopaint in Corel Painter, that prep work might be lost on the viewer of the final result.

That said it sure can't hurt to try. Regardless of the outcome, you're further along knowledge-wise than not having given it a go.

Should look good.
Those "zoned" (is that really the word?) images already look a bit "non-photo-realistic".
Making them "arty", and so a little more removed from reality, would probably make them more pleasing to the eyes. (avoiding the "uncanny valley")