I was wondering the same thing. It seems that there are people inside the FBI that are working against each other and there are a lot of loose canons mingling around. I don’t think I put that very well but I’m confused, too.
One theory: Mueller sponsored the investigation, but was told by Obama/Clinton/Holder to shut up and play ball so the uranium deal could proceeed. Perhaps he is being offered immunity now so he can bring the whole corrupt thing down?