Assuming there's no obvious visible outer problem with the filler neck, then it's possibly some foreign object has somehow found its way in to the neck...ie maybe the little flap that the fuel filler nozzle pushes down, maybe one of these collapsed and went down the neck and was replaced without fishing the now disappeared one out.

Maybe a peruse on the three make's specific forums might reveal a reason, someone there will have had to remove/refit the filler neck and hopefully posted a thread about how to do it.

Unfortunately the car had an accident on that side, and it wasn't repaired to a great standard. I've got a feeling the dealership wouldn't want to touch it. It may tie in with the idea of some obstruction though, following the shunt.

If the damage was in the area of the fuel filler,then it is possible that the plastic filler neck to the tank and/or breather pipe is damaged,kinked or incorrectly fitted.

As the car is so new, the damage may well be implicated.

I have an old MX5 that takes 10 minutes to dribble the fuel into. I have been told the problem is a blocked tank breather tube, but as it is buried somewhere failry inaccessible I have not investigated yet...I tend to choose quiet filling stations as people waiting can get quite impatient!