A Cook County judge dismissed a lawsuit filed by the owners of a Joliet casino seeking damages against a kitchen exhaust-cleaning company they say was the proximate cause of a 2009 fire that destroyed part of the casino.The former Empress Casino in Joliet caught fire when a welder began welding new ductwork to an existing duct in the casino’s kitchen. The existing ductwork was allegedly coated with grease and other residue from cooking, causing the fire to quickly spread out of control, according to court records …