After long search-well 30 minutes-15inch LT tires load E/116

I'm guessing maybe the OP is running at a higher speed than the 65mph rating for the Maxxis tires. Also unless you have 6 lug rims, I don't think anyone makes a 16" rim for a 5 lug bolt pattern. If you only have 7K split between 2 axles on a 5th wheel, it must be a super small under 30ft 5th wheel. Have you actually weighed your 5th wheel to see what the actual weight is??

Maxxis ST8008 warranty is for 6 years.

Subject to the limitations contained in this Limited Warranty, your new Maxxis tires are
warranted under this Limited Warranty against failures due to defective materials and
workmanship for a period of six years from the date of manufacture.

I've been running Maxis M8008's E rated for 10 years and have never had a blowout. I head to Colorado every August and cross the desert without a mishap. Make sure you run max pressure 80 PSI, low pressure causes any tire to run hot.

It is listed as an LT tire in the Amazon specs. and an AT in the page header. That is one of the reasons I was hoping someone had the tire. The reviews on Amazon are all good but no one has come back to report on the tire after several months or 10,000 or more miles.

I can likely get by with a D tire I used ST D tires for several years before trying the ST E rated Maxxis. But I like the 2700 x 4 capacity of these tires and the speed rating.

True the tread design can generate some more heat than a highway tire but I am running AT tires on the truck and it has not had a problem---YET. :) If I can find a highway tire with the same speed that will handle the load with some cushion to spare I would go with it. I will look at the Wranglers.

Exactly why I stay with LT's (Yokohama's great warranty)

More fodder;
your thinking correct on speed rating and long term reliability for tires on a trailer in those conditions.

Check out he Goodyear Wrangler HT in a LT215/75-15 D load range at 2096 lb capacity/65 psi with a Q speed rating.
Goodyear make over a dozen Wrangler tires so make sure its the HT type tread

Or a LT235/75-15 C load range at 1985 lbs capacity/50 psi with a Q speed rating...this tire is made by several usa tire manufacturers so it should be available just about anywhere.

Yokohama RY215 700R 15 load D. This is a euro size and made for vans/suvs and trailers.

Goodyear Cargo G26 225/70R 15 C 65 psi...another euro class tire made for trailers/vans/etc

I towed for a living in NM/CO/TX/OK/KS/LA/AR/MO so I understand heat from high ambient temps/road surface temps and high heat generated by different tread types.
I found a low rolling resistance tire tread like a highway tread (HT) or especially a ribbed tire tread like the Bridgestone R-250 run the coolest making a 12-14 hour run at interstate speeds in those high temps carrying max loads.
A AT type tread can generate more heat at interstate speeds.