We are told that he let it go because he had to spend money on...

We are told that he let it go because he had to spend money on the tenements to keep them and without Native title he didn't want to spend anything on further exploration. And he had LD to go with.
But the issue with Native title, we were told, was more about how CDNTS wanted to go about business rather than the trad owners per se. Native title was probably achievable providing CDNTS saw some cash upfront.
I think we all know that MR let MacKay go because the resource was inferior to LD and the location was no better than LD. This is still the case.
AMN jumped on the tenements because they had done research on RWD and saw how profitable SOP could be. They took what was essentially a shell company and set about becoming a SOP company initially by stalking RWD into the little Sandy desert.