The independent investigator will have all the witnesses interviewed again, and may revisit some witnesses in light of statements by others. It's not just a matter of reviewing existing material, although that is, of course, part of the process of getting as much "truth" as is reasonably possible, before applying the law and reaching a decision.
I don't think the independent investigator is afraid - but will be careful about how to present the conclusion and findings, so as to be most credible.
I respectfully disagree. They have had more than enough time to go over the case 10 times. Lets face it if they had enough evidence they would have already take Mr. Zimmerman in.
They don't have enough and don't know how to handle this since the LSM has tried it for them.