2004 WINNEBAGO ADVENTURER Engine And Engine Cooling Problems

I OWN A 2004 WINNEBAGO ADVENTURER WPG38R. I INCURRED WHAT AMOUNTED TO A PREMATURE FAILURE OF THE EXHAUST SYSTEM ON MY ON A GENERATOR, DIRECTLY CAUSED BY WINNEBAGO IGNORING ONAN'S "RECOMMENDED" INSTALLATION INSTRUCTIONS. THOSE INSTRUCTIONS SPECIFICALLY STATE A SUPPORT BRACKET BE INSTALLED IF THE TAILPIPE ASSEMBLY IS MORE THAN 18" LONG. THE TAILPIPE ASSEMBLY ON THIS UNIT IS 25" LONG. THE FIX, IF CAUGHT EARLY ON COST ME $725.00. MY REAL CONCERN INVOLVES SAFETY. ONAN WARNS IN THEIR INSTALLATION INSTRUCTIONS " A HOT EXHAUST PIPE CAN CAUSE ---- SEVERE PERSONAL INJURY OR DEATH. I ALSO ASSUME IT CAUSE CARBON MOXIDE POISONING OR HEAT/ FIRE DAMAGE TO THE MOTOR HOME. WINNEBAGO PUT IN WRITING TO ME THEY HAD ALL THEIR MODEL YEARS INSTALLATIONS APPROVED AND INSPECTED BY ONAN.. ONAN PUT IN WRITING TO ME THEY DIDN'T APPROVE OR INSPECT ANY INSTALLATIONS FOR ANY CUSTOMER. WHEN CONFRONTED WITH THIS INFORMATION, A WINNEBAGO...