Sam, regarding this you wrote " I have not stopped about the subject of the beach. The confusion about that persists ". The only person here that is confused about what trail these singers hiked on, and where they were singing is you. Regarding the beach area across the stream from the hot pools at Deep Creek Hot Springs where these girls sang, I think its well past time to put your confusion to rest:

http://iheartmoosiq.tumblr.com/post/21928031397/soko-and-a-water-less-adventure

Notice at this site what it says......" The video was shot in the Mojave Desert at the Deep Creek Hot Springs "

And this site shows a photo of Soko up at the Bowen Ranch parking area, where the girls hiked in from:

http://bust.com/blog/watch-soko-how-are-you-in-mojave-desert.html

Still in doubt? If so contact Soko yourself at this website and ask her what trail she and the other girls hiked, and where was the beach they did the video on:

http://www.sokopages.pixel51.com/