First off, the spa came from Utah in the first place, so it has already made that journey.
Second, I would not contact Bullfrog about how to move it. I love my Bullfrog spa as well, but my friends had a horror story with theirs.
Bullfrog shipped theirs to the dealer, but on the way the truck got in an accident. Bullfrog ships their tubs FOB Utah. Meaning that the dealer takes ownership the second the truck leaves the Bullfrog dock.
The truck it was on got impounded, because it was in an accident, the tub was on the truck for weeks. Bullfrog was like - not our problem. Then when it was released, it was damaged. Again, Bullfrog said, not our problem, have the dealer fix it and then put in a warranty claim. My friends were concerned about damage they could not see. The dealer was trying to figure out how to pay for all of this on the hope that it would eventually be reimbursed by Bullfrog. It was just a mess all around.
But, if money is no object, then as
@RDspaguy said, I would go with a Hotshot over LTL. One that maybe has a good reputation.
I mean, heck, if you can get your company to foot the bill, go FedEx Custom Critical.