I haven't either, but have you seen many people share their experience of working with him? I haven't.
I've worked directly with Sam on a few projects, and was always impressed by how thoughtful and empathetic he was. I've worked with a number of smart, wealthy people, and Sam is the only one I'd say that about.
The board may know something nobody else does, but I think (given the current information) it's significantly more likely that they _are_ who they purport to be... it's just that the board wanted something different.