Ford Falcon 2004: Rust bleed

FIVE weeks ago I bought a 2004 BA XT Ford Falcon. It was in immaculate condition, with all log books, had never crashed and had 130,000km on the clock. But I have discovered it has rust in a number of areas. After reading the owner's manual and warranty booklet to see there is a five-year rust perforation cover, I took the vehicle to a Ford dealer and was advised to take it to their approved crash repairer. They would photograph the rusty areas and send a report and quote to Ford. The crash repairer told me the rust is common and he had repaired many in an even worse condition than mine under that warranty. My claim was rejected by Ford, stating my vehicle has corrosion bleed, not perforation rust, which is not covered under the warranty. The crash repairer couldn't believe it and told me the rust was coming from underneath the paint in some areas and in others the seams were not sealed correctly at the factory. He suggested I put pressure on Ford to reconsider. They are holding fast to their decision and I am unsure what to do.