If you have a business involved in export, it’s easy: when you sell a product or service outside SA, bank the revenue outside, and pay your people with your inside-SA assets, until you have spent all your inside SA assets.
Then, you can provide a service to other white South Africans: invest money in my company, and get revenue deposited outside SA.
I wonder if people purchasing safaris in South Africa pay for them into Panamanian accounts...
I know someone who did that when they left Shrilanka. He manufactured Cricket bats overseas, bought his own product and sold locally. Easy transfer of his wealth to an overseas firm. Didn’t get all his money but got a lot more than the government wanted him to take.