Massive WEDI Shower FAILURE (Done by Certified Installer) -- Warranty Claim DENIED

I was contacted by a homeowner to come out and look at his WEDI shower, that was built in 2007 by a certified WEDI installer. The company that performed the work went out of business since then. They were a medium size tile installation company that did residential new construction (track homes) and commercial work.
So the homeowner contacted a tile contractor who used to work for that company before it went out of business. Through the contractor, WEDI was contacted. They sent out a technician who gathered information, they sent it back to WEDI, and the warranty claim was denied.
See below for an explanation of the denied claim:

"....The shower was subject to movement, explaining perimeter and generally grout cracks, also at the bench. Such structural movement particularly destroys weak seals such as those present at the bench. This leads to water exposure of the bench construction, and the floor. Such exposure causes not only rot, but increases movement to an extreme level, amplifying the original issues."

Please let me know if anyone else has seen or heard of failures such as this. The more information that is out there, the better we can help our fellow tile installers decide for themselves what is the best method to use.
Leave your comments in the section below. Please try to be helpful, even if you do not agree with me. I am ok leaving negative comments up as long as they are helpful in any way.

Видео Massive WEDI Shower FAILURE (Done by Certified Installer) -- Warranty Claim DENIED канала TileCoach