I would submit a 3rd possibility, though it could be seen as a subpoint to your 2nd point, and that is that a general sticking point on previously failed negotiations was lack of ability to clearly see the deposit.  If this scenario is correct, it is unknowable if doing this would bring those particular suitors back to the table, but it may help seal the deal with future suitors.  I agree, though, that this wouldn't be done out of the blue.  It clearly is being done with a strong belief that it will help move Hay Mountain forward.