Having an audit done is only going to restore confidence to the market if the gold is actually all there. I give it a greater than 50% chance that it's not, and that becoming public knowledge would be catastrophic for the markets.
It really says a lot about this world when an underground vault containing Shrodinger's gold which either way will not be used for anything other than sitting there doing nothing, will cause such such a dramatic outcome if it is observed.
It is what it is, but the audits not happening for so long make me think the gold is gone. No one is ever going to steal it with a direct guns blazing robbery so stories like 'thieves may learn the layout if someone goes in to audit' are very silly excuses. Does anyone genuinely not see that a very, very lengthy period of 'That extraordinarily valuable stuff I'm guarding is totally still there, but I won't allow you to check, just believe me' is reason to think it's likely not there?