Incorrect.
Considering that Shuttleworth sold Thawte for hundreds of millions of dollars (and hence billions of Rand), the RBSA held the money on his behalf. Don't for one second believe that he kept it in his Joe-Average cheque account at ABSA, First National, Standard or NedBank... Considering that his billions would not have had any standard deposit insurance at *any* consumer bank in South Africa, RBSA was the only place to put it.