The article says, “Even the planes flying over have a difficulty looking down in the corn rows.”
Possible application for Lidar? Seems to work for finding lost prehistoric structures in the jungles of central America.
If her FitBit and mobile phone data wasn't helpful, Lidar won't work. Unless the dog ate her, it is likely that she was abducted and killed, and her body may or may not show up, ever. That's three crime scenes -- abduction, murder, and disposal. In a rural area, it'll probably be either the nearest male neighbor to where she was dog-sitting, or someone along either the jogging or dog-walking route.
“Possible application for Lidar?”
I would think so! I believe that there are drones available with Lidar - as well as thermal imaging. Obviously thermal is good for a living, warm body. But also a deceased body would have different thermal properties than the soils around it. Scan after the sun has set, or before it rises.