Frank Vennes Jr., a Shorewood businessman who has been linked to an investment fraud scheme allegedly run by entrepreneur Tom Petters, got court approval Thursday to sell his Florida mansion for $5.8 million. According to the government, Petters enticed investors into giving him money by telling them it would be used to buy merchandise that he would then resell for a substantial profit through big-box retail chains. The government says that the merchandise never existed, and that Petters used the money for other businesses, to make lulling payments to investors and for his lavish lifestyle. Vennes, who has not been charged in the case, has told the FBI that he earned millions of dollars a year by referring investors to Petters.