[SLS Artemis]

If I had more time, I would buy a cheapest part that is available, probably that piece in between the doors, and leave it out somewhere away from any window and in a spot where someone wouldn't find it and see if it melts. I would bet it would. I bet it melts simply because it is poorly manufactured. It would also confirm that solar convergence isn't the reason for the melting issue.

I am wondering if there is a window reflection from the sun that is occurring perhaps from your house or the neighbors. There are cases of vinyl siding melting because of a magnified light reflection of the sun from windows in many cases.

I saw some siding on a house that was absolutely fine for a long time. They painted it a dark color and it melted quickly.