Pictures would be helpful. Where is it worn, inside, outside, middle, all over? Did you check pressure before towing? After? What was pressure? When were tires put on? Was it worn when you started out? How far did you tow?
Couple of things to check- hub center to hub center difference between tires on left and right, jack up trailer and check angle of arms holding hubs. I don't know the correct number, but you can find it or maybe someone will comment. If they are not close to the same, one axle may be overloaded because others aren't carrying their share of the load. Also tire pressures should be balanced, or the one with the higher pressure will carry more load.
Others may have more ideas.
You dodged a bullet, could have been bad if tire disintegrated.
"You cannot reason someone out of a position they have not been reasoned into"
Al, K5TAN and Missy, N4RGO
2002 Classic 30 Slideout
2001 Safari 25 RB Twin (Gone, but not forgotten)
2013 Dodge 2500 Laramie 4x4 Megacab Cummins
WBCCI 1322, TAC FL-39, AIR 82265