Yes, both of those stories are true.
During WW2 the Crown harvested a lot of the timber on the Balnagown estate for the war effort, and applied the money they owed for it against Sir Charles's tax debt (by then Ross was dead, of course). So once the war was over his third and final wife was able to return to an estate largely free of debt.
Some years ago I examined a file in the Public Records Office and made a note:
FO 371/61111
Correspondence relating to the Balnagown Estate (in liquidation), property of the late Sir Charles Ross, and various properties in it which were requisitioned under wartime powers so they could be farmed more efficiently. Scottish Department unwilling to give them back and intends to let them to new tenants.