Possible heat and/or hydration problem.
The water team returned with two gallons. The cell phone team was unable to make contact, but spotted a well-used two track in a nearby wash. In the meantime, the patient began to urinate copiously. A few hours later, she was still weak but able to stand.
The group stayed hydrated, rested, and ate through the afternoon. Eventually the patient said she was thirsty and began to drink water spiked with some salt. In the cool of the evening the group walked slowly with the patient to the two track when, with a stroke of luck, they ran into a fellow on a dirt bike who was able to head to a parking lot and return with an ATV and give the patient and her companion a ride to town.