Jay,
My 1st thought was to just use an evaporator panel (canvas, burlap,..) with the bottom in a water-filled tray, fastened to a window screen, to let the prevailing wind blow though, instead of a fan. Assist could be with the MaxxFan on exhaust mode. (Yes, Winds: that's why there are so many wind-power farms there.) That's how Death Valley Scotty cooled Scotty's Castle.
2nd thought was, NO. Those winds move a lot of dust, dirt, and sand.
I've camped and explored in the the northern Mojave Desert (north of I-15, to the Tehachapi and Sierra Nevada mt. ranges) for 60 years. From May to October, you can have 100°F temperatures from 11:00 am to nightfall at any time. An evaporative cooler will typically maintain 80° temps. So, boondocking is possible if you can accept the conditions. For respite from the heat and winds, expect to be hooked up to power, so you can close the windows and rely on A/C. In our Escape 17, the A/C can maintain 75-78°F when it's a dry 110° outside. We do take the following steps: parking with the door side facing south and the awning partially extended (shade), with straps at the awning corners secured to ground anchors (wind precaution). That provides shade for the refrigerator-side of the trailer, with only the back of the trailer in direct sun.
Generally in the summer, we go up into the mountains. To escape summer heat, we will be at 6000-7000 feet elev. to find 80° temps. (At 9000 ft. it's a nice 70-75°
).