That looks more like the cell lifting and constantly rubbing on the corner of the tab than from a fuel nozzle. First thing I would do is to put a good radius on the two corners of the tab before it's reinstalled.
Now, to lift that much and cause that kind of damage, at least to me, it would appear you have a vent issue that's causing the cell to collapse from the bottom up since only fuel and the weight of the material holds it down. It is normal if the tank sits empty for more than a couple of weeks for it to lift some, but that will go back to normal once fuel it added back.
You need to investigate the entire vent system, especially the vent drains at the root of the rear of the underside of the wing. If they are not positioned properly, ie. they are bent back, they can cause a severe vacumm in the tank causing it to lift. You would also see fuel loss if this is happening. Conversly, if the vents are positioned too far forward, it can pressurize the tank much more than it's designed to be.
And it's odd that there is no additional rubber pad on the inside of the cell. Most new cells I've seen in the past 20 years, including the ones I installed in our S model long ago, have an additional rubber pad installed directly below the fuel port opening to prevent fuel nozzle damage to the cell itself.
What brand bladder is this ?
