I've had lots of blowouts and run flats on my equipment trailers when I was on the road.
That many sidewall cuts can be made after the tire has lost its air and running flat. The sidewalls flex and distort especially as your bringing the rig to a stop or low speed. The wheel simply starts cutting into the sidewall at all angles and will cut the sidewall into pieces as your slowly rolling along trying to reach the exit on down the road.
I wouldn't draw any conclusion to sidewall cuts when a Tire has been ran flat that long.
Looking at .gov tire complaints website has a few Carlisle RH tire complaints however not much in the way of knowing what actually happened.
The Carlisle RH haven't been out long enough to draw any long term service record
This from Carlisle webpages;
Carlisle RH production date..
*Launched in early 2013, the Carlisle Radial Trail RH Radial Trailer Tire for Toy Haulers, Boat Trailers, Cargo Trailers, Utility Trailers, Stock Trailers and other towable applications. The new and improved second generation Radial Trail RH combines two new Carlisle technologies.*
I would have a tire tech you trust remove the tire next to the flat tire for a look see inside/outside the tire for damage.
