Carrier/rack problems of the 2015 Lincoln MKT

2015 Lincoln Mkt has had two forward sunroofs shatter since I purchased the vehicle in July of 2017. The first occurred when a stone kicked from a truck tire struck it. But the second incident occurred with no such traffic around my vehicle. The glass shattered as I heard two loud cracks within about 5 seconds of one another. Again, I observed no traffic that would likely be the source of a thrown stone, and indeed, observed no objects inbound to strike my vehicle. The nature of the second sun roof's break leads me to believe there is a severe defect in the replacement sun roof (presumably sourced from Ford/Lincoln, given it's expense and the time required to acquire it).

While driving on city street, the front section of the moon roof exploded with a loud bang and created a crack in the glass from side to side. On the drive home other cracks developed along the driver side edge. Took it to a dealer the following day and was told to "call your insurance company!". On the way home from the dealer the roof shattered. Called Ford and was told that they would not cover glass.

I just got 2015 Lincoln Mkt livery package on 07/14/2015. I found the sunroof screen fram has a crack in four places. I belive this may cause the screen to drop to my passengers or cause injury. I take it to the nearest Ford service center they sayed they don't belive it is safety issue.