Adaptive Equipment problems of the 2006 Mercedes Benz E350

I own a 2006 mercedes e-series with 47,000 miles. I have noticed a fuel smell when the car is in the garage after refilling the tank. The problem was recently diagnosed as a faulty fuel tan seal. The dealer has indicated this is a dangerous condition and the car should not be driven. The estimated repair cost is over $600. In researching this on the internet I find this is a common dangerous problem but there has not been a recall. I also find that in instances where the seal has been replaced, the problem reoccurs a short time later and it is related to the entire mechanism, not just the seal. I feel this issue should be addressed by mercedes and plan to report this to the NHTSA. Please advise.