"I can't be entirely sure. The desert in at least one case, but..."

Nadine shrugs helplessly.

"If you have any idea of the general area...I may be able to find some more information. And track them. As long as you have something that smells like either of them. Claude would probably be best, I know him better than Sylvain."

And therefor is more acquainted with his scent. It's a long shot, but...she has access to the keen nose of a predator, may as well use it.