If it was me, I would take the hinge off and lay it on a hard surface and beat a 1/2" of arch out of it and see if it fixes it. If it did, I would even contemplate heating it up and cool it down with some water to temper it some. I know people will disagree (understood) but it's just my nature to experiment on things before giving up on them. Also, check the mounting to pillar holes and make sure they are not oblong instead of round. Your added pics do show the hinge up snug to the pillar. Lastly lube up those mounting pins on install.
Go easy on me guys lol.
