Welcome, Freefall. Unfortunately, they specifically prohibit swapping permits like that. They are extremely sensitive against scalpers playing games. Yosemite campground sites were subjected to that mess in the past years, and they want to prevent that.
I see you are from NC, so it may feel like too big a gamble, but you could schedule a trip, and come out and pick up the unused noshow permits. If you set yourself up to hike mid-week, you can practically be guaranteed of getting the permits you want.
Just google "unused whitney permits"
