Update-
Here are some pictures of what we found-
Lots of frost-in 2 weeks-
Pulling 1" strips of paper out of the door in the closed position revealed no resistance at all in the area defined by the masking tape strips
We built up a thin black weather stripping (behind the factory seal) until the paper strips had resistance- when pulled out in the shown affected area. It ended up with almost a 1/4" gradual build up in the corner area. We tapered the seal material as we got closer to the corner.
If you look close you can see the lower portion of the seal protruding inward.
I'll post progress on this fix as time goes on. PPL wants $195 plus shipping for a new lower door.
I tried the hair drier bit but no success-

. I think 1/4" (or more) in the corner was too much to correct with a warped door, or whatever might have happened to the door/seal.