At first I agreed that her temps seemed alittle high, but since your vet recommended it I would follow his advice. He may not specialize in BP's but as you stated he is a certified exotic animal vet; not just a typical dog and cat vet; and most likely has alot more medical training than any of us on here.
As far as her wieght lose goes it could just be from the stress and her numerous regurges or something else such as a parasite. Did he do any testing for parasites or anything else that could cause that much weight lose or just give her the antibiotic and antiparasitic injection?