Eliminating a large amount of excess cash via increasing the regular dividend payment would be very unusual and would be obviously unsustainable once the cash pile is drawn down, so I don’t think the market would reward that strategy with a higher share price at all. If anything the share price would be punished and management trashed for choosing the worst of 3 possible ways to return excess cash to shareholders.
Since MHJ is already paying out a high ratio of net income as a regular dividend, then the two ways to return the large amount of excess capital to shareholders is either via a buyback or via a one off special dividend. MHJ chose the buyback route.
If there are actually large shareholders exiting or reducing positions - then better for the buyback to be in operation than the alternative (share price dumping as there would be no demand for the large amount of shares being sold).