Maybe they called it a "sweat box" to avoid being called appropriators? I don't know. But the picture with that article is of a clean, white canvas yurt. Yurts are tall enough to stand in. What is being shown in the crime scene footage in all the other articles, and the 911 call videos, is a much lower to the ground, tarp-covered structure that, yes, seems to be their odd idea of a huge plastic sweat lodge.
We're discussing it over in this thread:
http://www.newagefraud.org/smf/index.php?topic=2380.0