Carol, your mention of 97deg. and 12% humidity triggered my fading memory of living in Utah (well, I just got back from 2 weeks there but . . ). We cooled our house there with an evaporative cooler, aka 'swamp cooler' instead of air conditioning. It's basically a big metal box with a large fan in it, vented on the sides with fiber pads that water runs down, so the air is pulled into the box by the fan through the wet pads and blown out into the house. They don't work where it is humid, but in low humidity they are excellent and they also *raise the humidity* as they cool. Even on a blazing 100+ day in Utah we used to be able to keep our 4 bedroom house down in the 70's all afternoon.
Just wondering if you might tryt a small swamp cooler for your orchid enclosure, just for use when those conditions arise. I've seen small 'room coolers' at Costco meant to be mounted in a window or small opening. You'd just have to figure out how to get a water supply to it. Initial cost, no idea but if you take into account replacing dead orchids over the years it actually might save you money in the long run.
