Utah designates 91 as Premium. Most high elevation places won't sell 93.
If you check a list of U.S. states by standard octane ratings it will say that Utah is 85/88/91
A competent off-road shop will have no trouble.
Sounds like your dealers just don't want to do it.
My '25 took the Eibach Stage 2R without issue or warning lights.
Great kit, really happy with the ride.
EDIT; I don't have Dynamic Bendy Headlights; the off-road shop had to adjust mine with a...
ChatGPT gave me some lab advice yesterday that, if followed, would have resulted in at least my own death and likely the death of a whomever came into the lab to discover my body (and that ChatGPT is a bad chemist.)
YMMV but don't believe everything you read on the internet.
Stock Tremor felt like a floaty boat to me. I tried the 5100 Bilsteins with the OEM springs but it didn't offer enough of an improvement. Ended up replacing everything with the Eibach 2R, really happy with the result. Rides much better on street and on the washed out back roads I need to use.