Even with the very low mileage, a blowout is still a blowout, and could cause an accident within that 22 miles. I experienced a sidewall blowout with the trailer just sitting over the winter on GY Marathons that had a date code 7 years old. Would agree with the 5 year limit on tire life, no matter how good they look. Age, not wear, is the killer of trailer tires, because they usually sit still much longer than they roll. JMHO
2003 Ford F-350 V-10 Crew Cab 4WD Long Bed
2004 Jayco Designer Medallion 29 RLTS 5th wheel
Bill, Gayle, and Mindi (dachshund)
Retired at last !
Nothing is foolproof to a sufficiently talented fool.