Tire Blowout problems of the 1999 GMC Sierra 2500

Employee driving 1999 GMC 2500 pickup towing a 2008 towmaster trailer loaded with a bobcat 325 Mini excavator northbound on I-25 at san felipe exit heard a pop, thinking it was a blown tire, tried to pull off to the right side of the road. Lost control of the vehicle, hit a passing car, hit a guardrail, crossed over the highway through another guardrail, down the concrete embankment to the road below. On the pickup both front tires were blown out as a result of landing at the bottom of the embankment (dot #k2w8yd4a, dom ???? country of origin: vietnam). Right rear tire held air, but tread was peeled off(dot# 4tw8yd4a, dom 0806 country of origin: china). Left rear tire (dot# h2w8yd4a, dom 2906, country of origin: korea) remained intact. All tires on the pickup were kuhmo road venture at - lt265/75r16. The right front tire of the trailer was also blown out. As a result of the accident the truck, trailer, and equipment were all totaled out, although thankfully the driver walked away with neck and back injuries. Driver and passenger of other car also received neck and back injuries. All tires were checked for proper tire pressure before the trip from las vegas, nm to albuquerque, nm and again reinspected before leaving albuquerque with load back to las vegas, nm.