Engine Shut Off Without Warning problems of the 2009 Nissan Maxima

My family and I were driving south bound on the new jersey turnpike at 75 mph and the car shutdown, it would not accelerate and lost power. Luckily we were in the right lane and I acted quickly to turn on the hazards and get off the highway on to the shoulder to avoid a serious accident. This car only has ~16000 miles as well as all of its scheduled maintenance is up to date. After getting it towed to the Nissan dealership they informed us that it was a problem with the mass air flow sensor and that even though the car was within the warranty period the warranty would not cover it as they found a leaf in the sensor. We have no way to verify that there was a leaf in the sensor and the car is kept in a garage and/or driveway nowhere near a tree. We wanted to report this incident so that if more incidents like this occur maybe a recall is warranted as Nissan's engineering of the vehicles could be at fault. How could a leaf in get in there? if a leaf does get in why would that corrode the part?.