Other Fuel System Hoses Lines/piping, And Fittings problems of the 2011 Chrysler 300

Check engine light came on 2 blocks from home. Parked the car. The next evening we could smell gas from our front porch, ten feet from the car. Curious we opened the car and the passenger compartment was pungent from the odor of gas. Called aaa and towed to local car repair. Plastic cap on top of the fuel tank located below rear passenger seat failed, access to 2nd fuel pump. The plasic failure allowed gas leak. The repair shop indicated the plastic cap appeared deteriorated from fuel. We had the pump and cap replaced. Very concerned about the material in the cap, and the danger in the passenger compartment for consequential gas leak.