Correction: the Rand has NOT broken through "R15 to the dollar" -- it's currently R15.2129 to the dollar. In other words, it takes R15.21 to buy one US dollar.
The writer of the article seems quite unaware of the difference between Buy Rate and Sell Rate. The sentence in the article says "R15 to the dollar" so he is talking about Sell Rate. And the wrong rate is quoted.
If you are buying Rand (ie converting US dollars to Rand), you will get R14.6957 for each US dollar.
If you are buying US dollars (ie selling Rand), it will cost you R15.2129 for each US dollar you buy.