SilverGate's tire repair was properly done following standards developed by all tire industry vested parties.
Meaning a group including tire manufacturers, tire repair manufacturers plus automotive and trailer manufacturers agree on proper repair products and procedure to safely restore the tire's performance capabilities.
The discussion of the tire's age at time of repair is another factor and the trailer tire industry does offer guidelines.
SilverGate claims the original 6 year old tires were replaced and the replacement tires were 3 years old when this puncture was repaired.
According to Carlisle Tires | Trailer Tires | | ATV & UTV Tires | Lawn & Garden Tires | Carlisle Belts
> Media> Downloads > Trailer Tires, it is recommended that a trailer tire has a life of 3-5 years and claims that at 3 years of age a trailer tire has lost about 1/3 of it's strength.
This is why beginning at 3 years this owner should question just how much to invest keeping those tires in operation. The repair is cheap compared to replacing the tire which can be done at a more convenient time either soon or much later if the owner chooses.
If one tire is replaced I think both same side tires on tandem axles should be changed if not all tires.
Another important factor is if the punctured tire ran low of air for any length of time! Sidewall heat can develop from under inflation and weaken the tire also/or the other same side tire in a tandem can overload by carrying more weight which now has weakened it creating a separate potential future safety issue.
This is why 4 years tends to be suggested as maximum age for a trailer tire regardless of remaining tread-life. Having the trailer in locales with more sun-light or heat is known to shorten tire life/strength.
Should a trailer tire be pushed to perform beyond it's recommended operational life is a gamble. A trailer tire blow-out can cause damage to the rim and/or body of the trailer and usually occurs during leisure time for the RV owner or during working hours for a business.
Do we really want this stress at an inconvenient time that some minor preparation could have overcome?