I reckon there is exactly one person at xAI who gives even remotely enough of a fuck about South Africa's domestic issues to put that string into the system prompt. We all know who it is.
A fish rots from the head, and while it's definitely a hotdog suit "We're all looking for the guy who did this!" moment, remember Musk is in charge of hiring and firing. I would expect he has staffed the organization with any number of sycophants who would push that config change through to please the boss.
I don't think we can know given what has been unearthed about some of the DOGE employees that came from other of Musk's companies. Not that it's unlikely that it's him.