Are ST tires now rated for passenger service? Was illegal not long ago, and Id suspect still is.
QC always suspect where liability doesn’t amount to much.
A travel trailer isn’t a construction materials trailer gets dragged around a metro. A failure isn’t the problem a TT experiences with a blowout. Not in damage nor time spent on the highway shoulder.
Non-ST is an easy choice thereby.
Matching load requirements to tire choice remains for research.
I used Yokohama RY-215 last time and may again.
Start with a scale ticket after loaded for camping, full fresh water + propane.
Use reality over guesstimates.
.