I'm not an expert but I've been told by the orchid grower near me that dens like to be planted with the media real tight in the smallest pot possible and let the media completely dry before watering again.
To me, yours looks like it's sulking, I don't think it's going to die...
Lots of patience is needed. I had a den that lost all of it's leaves (I'm still not sure why) and looked much worse than yours. It took several months before new growth appeared. I think yours will recover much quicker.