You're treading in the waters where people are drowing in lawsuits. No matter how creative you make it, the bank will find out if you sell short sale and in any way benefit from it. They employ people to specifically investigate things like this, and it's not too hard to figure it all out. There are people who pulled this kind of thing 2 years ago that have recently been caught, so they apparently check back longer than most people would think.
Be careful, and if you want to find a legal way to fool the bank I suggest getting a really good attorney, one that is willing to go to jail with you if things "don't work out".