I'm not sure. At first, when I read your post, I thought yes that's strange. After reflecting on it a while, I'm not so sure. Mr. Smith tried (or certainly appeared to try) to find her in Philly and continued his efforts while she was officially missing. Once the body was found, there was no further point in talking to LE. She was murdered, buried, and dug up by animals, and nothing was going to change that.
I suppose if it were me, I'd have gone to NC to see if there was any info I could share that would help local LE find the killer. But Smith may have figured he didn't have anything to offer. As for seeing where the person died, I don't know. I would want to visit the place, but I can understand that many people might not want to do so. Does every mother and father really want to go to Iraq or Afghanistan to see the exact spot their son died?
He may not have been able to face it.
In Smiths mind, the case may have been "over" at the point where he learns
she's dead. His experience as a lawyer may have told him the probability of finding the killer was low. Finding the killer wouldn't bring her back anyway. I can understand him just giving up at that point.
I bolded the above question.
The family of a soldier killed in action usually know the reason their loved one was in the foreign country and how or why they were killed. In the case of Judy, no one knows who killed her or why she was there. It is unexpected for a civilian to disappear and show up dead miles and miles away.
It is possible her husband was exhausted and depressed over his wife's
disappearance and murder. Maybe, he wasn't emotionally ready to see the scene of her murder. I wonder if her children visited the area?