There was recently an entire episode dedicated almost entirely to cadaver dog testimony. Well, the dog was not testifying, the handler was.
Now, I have no doubt that cadaver dogs can, and do, find cadavers, and can detect when a cadaver was recently present.
But listening to the testimony of the handler, from their viewpoints, the cadaver dogs are psychic. The ability of their senses verges on mysticism.
I don't doubt that there is value to cadaver dogs - clearly they work, and get results. But the humans who testify on the dogs' behalf have a cult-like behavior about what the dogs can realistically detect, and how they interpret the dogs behaviors.