If Nora had been wandering around she would have needed to go to the loo and surely that would have left strong scents for the dogs to pick up on.
If she had been out in the jungle for that length of time,would she not be covered in bites and perhaps leeches?
If she did get dehydrated there might not be a lot of waste elimination.
Also I still think there was a massive area to be covered and the dogs would probably be used closer to the resort trying to pick up a trail to be followed rather than taking such a small number of dogs on several kilometre walks fairly aimlessly through the forest.
If something like footprints or clothing scraps or anything suggestive of Nora having been present in an area was found by searchers, then the dogs could be taken to that specific place within a couple of hours depending on the ease of getting there, so I think that would be the best use of the dogs.
So the dogs might never have gone near the area where Nora was found if the searchers didn't find anything particularly suggestive up there that led to the dogs being called to that spot.
JMO