2012 Fleetwood Jamboree

I HAVE A 2012 CLASS C FLEETWOOD JAMBOREE MOTOR HOME ON A FORD E450 CHASSIS. THE FUEL SYSTEM DEVELOPED A LEAK WHEN I PUMPED GAS INTO THE TANK. THE LEAK WAS COMING FROM THE FUEL FILLER PIPE HOSE THAT RUNS THROUGH THE FRAME AND CLAMPS TO THE GAS TANK. THE FILLER HOSE WAS FACTORY INSTALLED. I TOOK THE MOTOR HOME TO A SHOP FOR REPAIRS ON NOVEMBER 16, 2020. THE MECHANIC REPLACED THE 10' PIECE OF HOSE THAT RUNS FROM THE TANK THROUGH THE FRAME AND JOINS TO ANOTHER SECTION OF HOSE ABOUT 11' LONG. THE MECHANIC SHOWED ME THE OLD HOSE HE REMOVED. THE HOSE WAS VERY DEGRADED AND HAD MANY CRACKS. THERE WERE SEVERAL LONG DEEP CRACKS ON THE TOP OF THE HOSE ABOUT 4' FROM THE END THAT CLAMPED TO THE TANK. THOSE DEEP CRACKS WERE LEAKING GAS WHEN I PUMPED GAS INTO THE TANK. HE SAID THIS SECTION OF HOSE WAS NOT FUEL GRADE HOSE AND WAS ACTUALLY HYDRAULIC HOSE. HE ALSO SAID HE HAD SEEN THIS SAME PROBLEM SEVERAL TIMES BEFORE. THIS CLASS C MOTOR HOME IS ACTUALLY BUILT ON A 2011 FORD CAB CUTAWAY E450 CHASSIS EVEN THOUGH FLEETWOOD SELLS IT AS A 2012 AFTER THEY BUILD THE HOUSE PORTION. THERE ARE TENS OF THOUSANDS CLASS C MOTOR HOMES ON ROAD ON THE FORD E450 AND E350 CHASSIS. I BECAME VERY CONCERNED WHEN THE MECHANIC TOLD ME THAT THE FACTORY INSTALLED HOSE THAT WAS LEAKING THAT HE REMOVED WAS HYDRAULIC GRADE HOSE AND NOT FUEL GRADE HOSE. I AM TOLD, I DON'T KNOW FIRSTHAND, THAT THE FORD CAB CUTAWAY IS DELIVERED TO THE MOTOR HOME MANUFACTURER WITH ONLY A PARTIAL FUEL FILLER HOSE INSTALLED AND THE MANUFACTURER JOINS ANOTHER PIECE OF HOSE TO CONNECT IT TO THE GAS TANK. I AM ALSO TOLD, AGAIN WITHOUT FIRSTHAND KNOWLEDGE, THAT ETHANOL IN GASOLINE WILL DEGRADE NONE FUEL GRADE HOSE.