I completely agree with Hoosierfan72's great post. I felt the same way about JP's testimony. How much of what they are saying is colored by their current suspicions about BM?
I think the riverside (in the water) deserves a much closer look. Is it shallow enough to use ground-penetrating radar?
Also...why on earth would LE ask for MG's phone? I don't recall JP mentioning giving up his phone. Yes, you can buy a pay-go disposable pretty cheap, but if LE has your phone, you've lost all your contacts, etc. Major inconvenience, IMHO.
For that matter, why would the two fellows who spoke to her be telling her that she did not have to give up her phone to LE if asked?
If that's all true, it sounds like perhaps something on BM's phone led them to want to see MG's phone. That might go back to the microexpressions when speaking about BM and her reluctance to take a lie detector test. She probably fears (and rightly) that they're going to ask her about things she doesn't want to talk about. For example, if she had a one-nighter with BM, she wouldn't want it to come out now, especially if it had nothing to do with SM's disappearance.