The Krog name was brought to South Africa by Johann Christoffer Krog in 1794. Johann Christoffer Krog arrived in the Cape of Good Hope on the Hertog van Brunswijk as an employee of the Dutch East India Company.
Johann Christoffer Krog had no intention of actually settling in South Africa. But this all changed when the journey back home to Europe onboard the Makassar took an unexpected turn. The unexpected change in circumstances left him with no other option but make South Africa his home.
You can read the story of Johann Christoffer Krog and the origins of the Krog name in South Africa in the article I wrote called "Johann to Johannes: A History of my Family".