I was a clerk to a federal bankruptcy judge while in law school many moons ago - trust me, there won't be anything to go after.
It's true that if there's evidence of a "preferential transfer" or undisclosed assets there's a chance the Trustee will petition the court to reopen the case. However, it is extremely rare that there's any meaningful amount of retrievable wealth to make it worthwhile doing so.
As a side note, one way to put additional pressure on the dishonest debtor is to contact the local criminal prosecutor and suggest that there's sufficient grounds for a criminal perjury charge. A call from the prosecutor's office to come down for an interview always wakes up a less-than-forthright dead beat debtor....