Forgot to mention: I've also seen all four "visions" associated with each frozen person, but the "spirit" on the far left still doesn't leave when approached. I'm assuming the order the bodies are discovered doesn't matter, as that would be silly, but maybe that's the issue?

Ugh. Code 18: I actually didn't see the vision associated with the frozen body in the garage of Lamothe's property. The spirit is free...what a great game...