That's a really strange story actually surrounding mexipedium. The original plants have been supposedly collected by scientists, yet they did not take any photo of the habitat.
I have seen a picture of a very tiny hill with a plant on it, and another 'close up' but those would not qualify for in-situ pictures, more maked up photos. I am sure that in the wild there should be colonies of few dozen or hundreds growths, looking at how fast it grows in cultivation...
Furthermore, the habitat is said to be 'secret', and the few informations gathered do not fit its way of growing - this species is definitely not exactly a complete xerophyte. There has been supposedly 7 different collected plants, some sources say 9, some others say only 2-3 clumps divided subsequently.
To my mind, owing to the interest in this species, if anyone knew exactly the source location, there would have been another paper showing in-situ pictures, or some studies of the populations, etc...
It is more than likely that, as for some other species here in Asia, some local or tribal people put those funny plants in a commercial collection, and when they were sold from market to market, the origin has been lost...