Former condo association treasurer leaves mess of her unit after sale

The condo association board treasurer who was selling her unit discovered a leak over her kitchen a week before she was closing on the sale. As a board member, I told her that she could get a contractor to do the repair work to the roof and her ceiling, provided she gets the licensing, bonding and insurance info for the company.

Since she has closed, we discovered the repairs done to the roof were not done properly, and the "company" that did it is in fact not a real company. Unfortunately, the bank told us that since she was a signatory to the condo association checking account, there is nothing we can do about having the check rescinded, etc. We have had absolutely no luck tracking down the company - we discovered that their invoice has phone numbers that are not real, and the insurance paperwork they provided is forged. The only recourse I see is suing the former owner/Board member for not fulfilling her fiduciary duties to the Condo Association and hiring a contractor with out getting the information required... Anyone have any thoughts or ideas?