I think they said they are checking cell records, but I don't know if they meant his or hers.
Yes, definitely. This is a rural area. The farther south you go, the less populated it is. There are houses along those back roads you're looking at- it's not all just barns and silos. But the houses are spaced pretty far apart. It's definitely possible for someone to sneak around through the back woods and not get caught. The moon is full, too, so that ads enough light that he might be able to see if he is on the run.
If you go really far south into extreme Southern Illinois, there are actually large wooded hills (or small mountains, however you want to look at it). The whole area is called the Shawnee National Forest. Someone could DEFINITELY hide out there. Thought I doubt he could make it that far on foot in such a short amount of time. It's a good 45 minute drive from Carmi; walking would take much longer.