Hi, I'm new here. I live about 10 miles from the cemetery and just heard about this case through a neighborhood FB post on the 24th anniversary last month. What a terribly sad and mysterious situation. I am so impressed by all the diligence and determination you've all expressed on this thread.
I had a couple thoughts as I read through Thread 1 and I can hopefully clarify some of the questions about the area. I've lived in the greater DC area since college in the early 1990s.
First, Nordstrom and REI are Seattle-based companies and were not common brands here in 1996, the only REI in this area at that time would have been a small store in South Arlington that typically drew only serious campers and hikers. I doubt she bought the backpack in this area, I feel this suggests that she could have been from the Western side of the U.S.
That said, JD had to have had firsthand knowledge of the Pleasant Valley cemetery. This section of Annandale is quite an unremarkable, nondescript, quiet suburban area, the strip of Little River Turnpike (LRT) is a divided four lane highway, no businesses, no sidewalks. If you didn't live here the only reason you would be here would be to pass through or go to the Northern Va. Community College (NVCC) campus, which is right across the street but set far back from the road. There are many cemeteries in the area, some larger or more historic, what I believe was the appeal is that PV has no lights at night but has a caretaker. There is a bus stop and crosswalk at a stop light on LRT for NVCC just a few yards from the area opposite the cemetery's main gates. (Search the satellite images on Google maps to see how it appears from the highway.)
Consider the date: Dec. 17. This is the week of winter solstice, it would have been dark by 5 p.m. here. Also, NVCC should have completed its fall semester and what normally would have been a busy bus stop would have been quiet.
So, I theorize that she planned her trip carefully by taking the bus (walking on LRT would have been very dangerous and she likely would have been noticed by many passing cars). If you look at the Google image of the cemetery, there is a narrow access road between it and LRT, the caretaker office is on the left, the mausoleum is on the right, close to the road but partially hidden by trees and a power substation that is surrounded by a fence. JD could have disembarked the bus at NVCC, crossed the road and walked a few feet past the fenced area, crossed the access road and easily entered the cemetery on the right side opposite the office, totally unnoticed in the dark. She made her resting place by the mausoleum and infant area, that might have been because she did not bring a flashlight that would have been noticed and it was too dark to go much further, also deer, foxes, etc. hang out in these areas. But she knew a caretaker would find her the next day.
Beyond that, it's all a wild guess. Perhaps she took a class at NVCC and noticed the cemetery or rode the bus through that area? Perhaps she listened to the other tapes while riding there? So much time has passed, I would be interested to know if the Fairfax PD could run the DNA through ancestry.com or other sites. But even if they miraculously found her name, we'd likely never learn her story. Maybe that's for the best... RIP dear JD.