Hmm...I guess I have to wonder if Cheryl wanted to commit suicide and didn't want to be found or identified immediately, what would make her think this culvert was the best place to do it?
IF this is suicide, the culvert seems like a reasonable choice to me. I can't begin to imagine what Chery's thought process was, if it was suicide, but the culvert gave her some privacy and time to carry this out without being disturbed. For someone who wants to be found eventually, as you say the culvert can be considered a good location.
She may have chosen to not do this at home because she didn't want her husband to be the one to find her, or because she didn't want to do it in their home where he may continue to live.
If she had chosen a different location she may never have been found. Her family and friends could have spent years or even forever wondering what happened to her.
All of that said, for the last several days I've been kind of on the fence but leaning towards suicide.
Yesterday that changed and I found myself leaning more towards homicide.
I'm not sure what kind of further evidence may exist that will cause me to be convinced of either.
Once again I really feel for Cheryl's family and friends.