Scottish Parliamentary Corporate Body conclusion paves the way for ex-first minister to give evidence to Holyrood committee.
Excluding staff time, total legal fees and expenses incurred as a result of the botched investigation totalled around £630,000.
Alex Salmond's legal team blasts the Scottish Government for providing 'partial and incomplete evidence'.
The pair were fined £2,500 each following a Scottish Football Association disciplinary hearing.
Lord Clark ruled that the dispute over relegation should be dealt with by an SFA -convened panel.
Wightman was ruled not to have defamed a wildcat conservation firm which he branded a 'tax haven'.
Lord Reed has been sworn in as the new head of the UK's highest court, succeeding Lady Hale.