It is not speculation that cold weather causes the creases...how are they going to fix something that changes with the temperature? I'd be very careful because they may think it gets fixed only to end up making it worse.
I'm glad someone at your dealership saw your problem and is attempting to make it right -- but they need to look at the underlying cause before they do anything.
There is a HARD insulation (I think it is a hardener/support and not an insulator) that is helping to cause the crease in the door, The shape of the crease is the shape of the end of the insulation:
http://www.forteforums.com/forums/f...oup-krease-kalamity-kulprit-known-crease.html
The "V" shaped crease on the top of the quarterpanel cannot be gotten to from behind. There is an inner metal skin that prevents you from getting to it. I would be concerned that any repairs would be negated the first cold snap you have.
Since I live in FL, and it stays mostly warm, when a cold front moves through and we get some cold temperatures the creases show right up again and then go away when the weather goes warm again. The door crease is very slow in disappearing.