The strip we used about 25 years ago to camp out at the (abandoned) hotel is still open, but there may be a steady stream of cars on it

I could tell you a story about landing on that 2 lane highway at night in a Scout towplane with a crazy French tow pilot, trying to find the parking lot of the Panamint hotel and get off the road before the headlights coming the other way got us... but you would never believe the story until I dug out the pictures.
Since then, I heard the hotel had been opened up for a while then closed down again. I am assuming the strip you're talking about is the one that was put in behind the hotel a long long time ago. Or did they build another strip somewhere in that area? Not much going on in Panamint Springs to my knowledge. No idea on the status.
You can try to contact SCSA, Southern Cal Soaring Association, they used to maintain a directory of the usable landing sites for gliders out in the desert. (I actually researched and wrote the very first version of that in 1984, loaned it to SCSA, and they never gave it back to me). They may have some current info or know someone who does.
Contact Caracole Soaring in California City, CA. Ask for Cindy. She also maintains an informal database of what strips are open, emergency glider landing spots, etc. If she doesn't know, she may know someone who does.