I had the same issue on my Charger of them catching and popping out, specifically on the driver side. There is a ramp on the back of the hinge arm that those plastic pieces slide on. Mine looked like something had happened to the ramp so it wasn't a smooth transition. it would slide to a certain point where the angle of the ramp changed and it would catch. I was thinking I would need to do something to smooth that area, but the car went to the shop before doing anything.
While getting ready to mount the new quarter panels, they found that the driver side hinge was bent, so they straightened it out. It will be interesting to see if that fixes it or if we still need to do something to smooth the area.
I would crawl in the trunk and check the ramp those pieces slide on as someone opens and closes the trunk. See where it is catching. I don't have pictures, but I found one online. Mine was opening to the point that the slide bushing was getting up where I have the red arrow pointing. Then when I tried to close it, the slide bushing caught on where the green arrow is pointing.
I don't know if the sheet metal ramp that bridges across there got bent, or if something else was wrong, allowing it to open too far. Either way,.... Look at that ramp area, and see how far up the bushing is sliding, and where it is catching when you try to close it.