Here is a pic of the right quarter panel you requested.
Even though others might disagree, I am going to have to take a stand on this one. Look at the area of your pic below the weld and to the right of the seam. That metal has been manipulated, pounded and distorted. This same seam is bellowed and/or thicker than a factory seam. There are also more signs of rust than in any other spot in this general area. Again...see if you can take a look inside the rear 1/4 behind the vinyl panel. Your answer should be quite clear.