Someone has to pay the back taxes. Not sure though if you could just pass this task off to the new investor you wholesale to or if it is due before sale.
Taxes create a lien on the house, which must be satisfied at close in order for title insurance to be issued. The seller typically pays these at close, and is deducted from their proceeds. The same would apply in a short sale. When the lender asks for a Preliminary Hud-1 or Seller Net Sheet, they want to know their bottom line: Offer minus taxes minus closing costs attributable to the seller equals net to the bank.
When you are working on a short sale on a subject investment, you must include all encumbrances on the subject property. All liens, mortgages and the like of.
It is best to see if you can negotiate a reduction of other encumbrances prior to the actual short sale negotiation as this can be a deal breaker in your short sale negotiations.
You can find a list of individuals who are filing for divorce at the courthouse, legal publication and or local newspaper.