The 'D' Zone is at the same depth as the S/E Zone and only 2 km West on the road that was built by Keevil.
No extra cost at all but 30% less value on the SE Zone and the S/E Zone has no deposit at this time.
Even Otto/Dan are not that dumb.
So, upon reflection, it seems that Otto/Dan were looking for rare earths, not Niobium, from the SE Zone for promotional purposes on the cheapie.
However, they never ascertained that the rare earths in the S/E Zone are deeper than a winkie can drill.
Another waste of money by Dan/Otto, not for the first time.
IMO.