As I said, I am also a german down here on a work permit, and I disagree with the entire "If you don't like it, leave story". I may not be South African, but I am fiercly proud of my adopted country (propably more so than my home country), I have a child on the way who will be South African rather than german, and as I pay taxes etc just like everyone else, I reserve the right to bitch and moan when things such as the situation Marcel is in crop up, or pot-holes in the street, or corruption etc. There are lots of foreigners here in ZA that add a ton of value to the country, and just for the fact that their paperwork is different, doesn't mean that they are not allowed to voice any criticism. I do not disagree with the fact that the laws of the country you reside in MUST be adhered however, but from what I can see in the thread, it's hardly a clear-cut case like driving drunk or evading tax for example. Leave the "don't like it, leave" stuff to the politicians.
Anyhow, back on subject. I understand you dislike having a partner in your business. Are you maybe married or have a Girlfriend of SA origin? There are a lot of options available to you in terms of SME finance that you could maybe explore in that case, the DTI in Pretoria is a good place to start. To get finance without a Permanent residence will be VERY difficult if you want to deal with anyone but private individuals, ie a Partner, and you may possibly arrive at the point where you will need to concede a bit on this.
In order to get yourself set up with someone like the DTI, your documents, especially a Business plan will have to be spot-on, and I'll be perfectly honest, if you can figure out a way to uplift even just one or two previously disadvantaged people by employing & training them, you'll stand a much better chance of obtaining some finance at very reasonable interest rates. And you'll get the satisfaction of helping some people with fewer opportunities than many others out as well, which is a very nice feeling.
In terms of the Partner story, you must also maybe consider that not all partners are the same, as they are all just people at the end of the day, so one bad experience shouldn't make you now say that all partnerships are bad, maybe it was just a bad partner, or a bad fit? And also consider that a South African partner isn't to be just a source of finance for you to do your own thing, but maybe can add some value to what you want to do? A good example would be someone with an interest in the Marine hobby who has a clue about Finance, Contracts and the Law, who can do that side of the work safely and honestly (as they have money invested) leaving you to do what you actually WANT to do, which is breeding fish? We have fallen on our face opening a business in South Africa a long time ago due to people cheating us in a partnership, lost lots of money and had to close shop; Since then we have found the right partners who employed financial people with administrative brains (which we lack, we are operational / marketing people), and our company is going from strength to strength, ie both parties are getting value from our arrangement for many years now. Just some food for thought, and although I disagree with the "Shut up or get out" comments, maybe another thing to consider is that sharing your clearly considerable and rare skills with some citizens of your host country is something to aim for as well, give something back to South Africa, after all, it's a much nicer place to live in than Germany IMO, and knowledge / skills is what is needed desperately here.