The reason they never came forward to say they suspected "Foul Play" is there was no evidence yet to support it. Even if they believed it...they needed something to point that way besides her vanishing before they were willing to say it publically. It doesn't surprise me they never said it up until the body was found. We are going to see more and more of this from LE. No more "suspects, pois, foul play, etc." in their vocabulary. It only means they feel they are being 'sneaky' and the actual perp won't know. :::rolling eyes::: (I guess some perps are that stupid!)
I think the "news" could have been the cell phone pings. The perp could have had her cell, even charged it, and used it...making them think she was still alive somewhere. It is a long shot, but it could have hampered them decifering all the towers and places after they did obtain the records having to go back to figure it out. They did say there were many areas they were drawn to search besides where they found the body. I took this to mean from the "cell phone technology", as he put it.
I would like to know the answer to this question, too. I keep wondering what happened during that period which gave them so much false hope. Did it give LE false hope, too? Or did they just let the family believe it?