I did that in the middle of summer on a set of well used tires. Cheap ones at that (master crap). Perhaps my trailer just wasn't as loaded as yours. I only had about 6000lbs between the crap in the bed and the trailer.

I went from michigan to Texas with my '94 ram 2500. Mostly straight shot, truck usually didn't shut off even while fueling, ate on the move, those tires just continued rolling down the road for a majority of the trip minus a 1 hour nap, some time to repair a trailer blow out, and later swap a tail light. The asphalt was hot, this was the middle of july. Tires were mastercrap 305/70/16 with ~25,000 miles on them. Trailer was set up for a good bit of tongue weight. Load range D.

Wait, I'm going outside right now to make sure they aren't E range, just in case.

They are mastercrap courser C/T D range 305/70/16. Not really a great tire, but I guess they suffice.  Not making a recommendation, just saying that went same distance(+) w/o issue. I've also had a nail in one for about 9 months, too worn off for extraction. Hasn't posed an issue, so it will stay there until I replace them, maybe end of the year.

I believe BFG builds a much higher quality tire, or would sure like to think so.

While it is right for them to do that, I also believe they would take the risk of losing a customer, in order to prevent the immediate loss of money. Guess it can't hurt to try. I will be impressed enough if they even replace the defective one. Not saying they shouldn't, would just be surprised if they don't try to find some excuse or try to cite some abuse clause ect ect.