Great post Coral, I don't think we should give up hope either, especially when we have no evidence of her death.
I did find this statement by LE in the Affidavit which explains how they viewed what happened to Lindsey and how that changed to where it was a criminal event in their minds. I think all this really says is that they stopped thinking she was a runaway and that someone committed a criminal act in the taking of her:
"It should be noted that the media and investigators did not believe Baum was the victim of a crime until the week following her disappearance (June 29 to July 3-4, 2009). It was initially believed she might be a run-away or had been injured and unable to get help". Affidavit
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