Hello Jan. I suspect that Mr Peter GLOVER had left the mine (if he was ever there)prior to 1899 as in the shareholders meeting of that year he was made no reference to. He of course could still be a shareholder, but not on the management. He also would seem to have left Australia as no death can be found for him.
It is odd that a reference was made to him being a "Millionaire" in the newspaper. That could have been a figment of his imagination or someone else's. Millionaire is a term relative to "Billionaire" nowadays. The disappearance of such a person would rate much more of a mention in the newspapers and proper searches undertaken. He would also have made much more of the news items, as he would have been one a vary elite number.
It was not uncommon to find people referred to as such, but in reality not quite so.
I wish you luck in your quest.

Neil