A lot of people on this forum are using the term "blow out" incorrectly; including the OP.
I can tell by the description from the OP that he did not have a "blow out." Having a blow out is an explosive event. The tire casing fails all at once and all of the air leaves the tire at once. It's very loud and very violent. Much like a cannon going off.
The OP more than likely had a leak caused by a nail or screw or whatever. He had a puncture that deflated the tire slowly. This caused the casing to heat up to the point of failure. The casing fails and sometime can cause serious damage to the trailer when it comes apart. Much, much, much different than a blow out.
The reason the right rear tire is the culprit most of the time is because that is where the trash on the road goes.........to the right side. The reason it happens to the rear is because the front will fling up the nail or screw and throw it into the rear tire where it punctures it.
This is the reason most people incorrectly think that ST tires are junk. They think they just "blow out" when in actuality the tire picks up a nail and they don't know it. They keep on driving until the casing fails from heat damage but they "think" they had a blow out.
A TMS will go a long way to preventing this kind of stuff.