It can hasten the process of identifying these chemicals if people with such a sense of smell present themselves to researchers. To me that's the most important takeaway of this story. Unfortunately, most articles reporting on the story bury the lede as the fact that people can smell disease draws more attention than what they're smelling, and that researchers either didn't seriously consider there might be such a chemical indicator or didn't know where to start until they had access to a super smeller.
This sort of diagnostic approach isn't new. Once upon a time doctors would taste urine samples! It just fell out of favor because machine and chemical tests are more reliable and consistent. But if you're not drinking other people's pee on a regular basis, or running a large scale, shot gun experiment (like a super smeller spending decades learning scents), initial discovery of such markers can become more difficult.