Your assumption is wrong. It is just dirt. Ask yourself, if it was as rich as they've said, why did not the PM world take notice? Why did they not process and sell it? It is supposedly concentrates, which would be a breeze to process?
Answer, it is dirt.
As far as Sheppard and the other new guys, they are very very naive...and know nothing of mining. As well, Sheppard's background is not as clean as has been portrayed. He is just as slimy as the rest of them, imo. Didn't know what he was getting himself into, and now, doesn't know how to extricate himself....
Also, who was at the helm when the massive dilution and unauthorized selling occurred? Sure, maybe Furlong fooled him, but he was the CEO, right...and should be held responsible.