2002 camry - vibration on fuel line near the tank

I own a 2002 Toyota Camry with 130k miles
The fuel injector rail has a screw which I am assuming that it’s solely purpose is to check whether gas is present at that location. A few weeks ago this screw became loose and most of the gas spilled. Luckily no one was hurt and the car did not go up in flames. After refilling the tank, I notice that the car is now making a low noise like a motorcycle muffler. The noise can be heard inside the car but not so much outside and it is frequency increases as the engine RPM increases. I got under the car and trace the noise to vibration on the fuel lines. The vibration is strongest near the tank. There are 3 or 4 lines but it seems that the one that vibrates the most is the one that is coming from the tank. I took the car to Pepb0ys. I explained the issue to the mechanic and ask him to touch the fuel line. He told me that the vibration was just the gas passing through the lines and that there is nothing to worry about.
Am I being paranoid? Or should I pursue this issue further? I know the car probably run on the tank reserve and I suspect that the fuel filter may be clogged. Should I have the car diagnoses even if there is no check engine light on? Or should I just skip the diagnoses and have the filter changed which is just a bit more expensive than the diagnose rate? Any other ideas of what may be going on?