I agree. I love you guys here at bp.net but I always stick to exotics vets' advice (who have actually examined the snake in question as well as talked with me in person) over that of people on the internet. Though it certainly doesn't hurt to get other opinions.
Additionally, if temps were raised after the snake was taken to the vet, the high temps are not the cause of the regurges (though there is the possibility that the warm temps have become a contributing factor). So I seriously doubt lowering temps would fix the problem.
Hope you figure it out soon!That is sure a lot of weight loss.