I have worked with enough of the non pens to know that there is only two ways that the non pen could have actually damaged the roof membrane. One way is if the tech dropped it on an corner onto the membrane, the other is if the tech put the bolts tail end pointing downward while building the non pen if its a non welded ready made frame.
DN resolved my complaint with the BBB and refunded me for the amounth I requested--which was about half of the cancellation fee. They cited the roof damage claim and the report of the tech. not showing up for issuing the refund.