Today followed a similar temperature range like yesterday, other than slightly lower max temp. Ambient only hit 90° per my phone and it was a hazy day. Not surprised considering dew point was mid 70s. I also set an outdoor thermometer against the fence directly behind the affected area so that it was west facing. It reached a max temp of 100° along with the white vinyl fence reading the same. I didn't bother to keep a log but did note that max temp reached was 124° for both corners of the pool liner from about 3:30 til 5. I last checked at 5:30 and they dropped to 121° and 123°, with the higher one being the affected corner. I forgot to check the concrete temp, but did check the siding temp on a west facing wall. I am using Certainteed Cedar Impressions for siding and it was 122° at 3:30. Everything seemed consistent to what I saw yesterday other than no 128° today. I did put new battery in my Fluke thermal gun though. At this point I'm fairly confident the readings are accurate. But like yesterday, no signs of any reflections in that corner.
On a brighter note, I did hear back from Latham and feel a bit more optimistic. My correspondence to them appears to have gotten their attention and they requested more info as well as any pictures I have. I know the PB who did the liner submitted the ones I sent him, but no idea what he told them. All I got from him was they denied the claim saying fading wasn't covered. Pfft...this isn't a fading problem.
I took a few more pics today trying to get a better close up. While doing this, I also ran my fingers over the affected area to see if I could raise the edges enough to show in the pics. That didn't do anything other than I could feel small pieces of print ball up on my fingers. Kind of a rubbery feel but too small to get a pic of. However on an even brighter note, I may have discovered something that proves my case even more. The ~peeling~ is only where the blue colored print is. If you notice in both pics, the diamond is not peeling, its still intact. But on both sides of the top point of the diamond, you can clearly see the blue print stops peeling just before the diamonds edge. If it was a chemical problem why is the diamond still intact. Same goes for the possibility of it being caused by a reflection or the robot.
Note- first pic is what I posted in my OP so you can compare it to the zoomed in pic