Hummm...this is some pretty esoteric stuff here. My first question would be, does it sound good? Cuz if it does, there you go. Go with it. But on further reflection, I think the question is this "isn't a sharp 9 the same as a minor 3rd?
In C, the minor 3rd is Eb.
In C, the 9 is D.
In C, the #9 is D#.
D# = Eb.


On a major chord, that would sound pretty dense and dissonant. Is that what you wanted?