This was the family farm they were searching, Crystal has been there no telling how many times in the past. Finding some small item of hers on the premises isn't going to indicate anything significant. Any defense attorney in the world would be able to explain that away in about 5 seconds.
We all know what they were searching for, and obviously they didn't find her. I would expect the lead investigator to be upbeat and positive about the search results, but that doesn't necessarily mean the prosecutor feels the same way. If they attempt to put Houck on trial with circumstantial evidence, and the jury acquits him, there won't be a second trial and the game is over. It's a risky tactic, and yes I know it's been done with success, but it's also been tried and failed on many occasions. In my mind, the worst thing that could happen would be for Houck to walk around a free man due to the double jeopardy clause. If you think he's arrogant and taunting now, wait until he knows he's untouchable by the legal system.
I don't know how many more times a judge is going to sign off on a search warrant for that same property..........probably not many.