A friend of mine was able to accompany them into the area around the 1st of the year. He was amazed how hard it was to access the area due to terrain and thick vegetation. Plus it rains a lot in the Olympics.
They have gotten some of the hair analysis back and some came back as unknown as he mentions.
I believe the process of the environmental DNA has been discussed in some of the threads here. Basically they take a core sample, such as the floor of a cave. Then run tests. The results are supposed to show all the various organisms that have used the cave. In this case though, as usual, it could come back as unknown, which is still good. But you are looking for everything that used the area. That would include humans. With this test contamination isn't really an option because the point is you want to know everything that was there. I assume the test is more in depth than a simple DNA test because you have to go far enough to actually identify what organism you're looking at without any idea what you are going to find. Of course the problem still exists, how close is BF DNA to human DNA.