2 Blowouts, different tires, different axles, 1 hour apart

Try a basic check for axle alignment. Measure from center to center of the wheels on each side of the trailer. If the two sides don't match, you have an alignment problem. There are several other measurements that need to be checked for proper alignment, but this is an easy one that you can do. I had a similar experience to yours. I found my axles were not aligned -- there was over an inch difference from side to side.

Bruce