Your question is lacking as to what you are attempting to claim. However, as an investor, you may be eligible for certain investment visas that will allow you to stay in the US and work for your company. You should contact an immigration attorney ASAP. Best of luck.
You can open a company under a B2 visa. You just can't obtain permanent residence or work for that company until you obtain a different visa.
The above is general legal and business analysis. It is not "legal advice" but analysis, and different lawyers may analyse this matter differently, especially if there are additional facts not reflected in the question. I am not your attorney until retained by a written retainer agreement signed by both of us. I am only licensed in California. See also avvo.com terms and conditions item 9, incorporated as if it was reprinted here.
Need more information to answer this question it does not end with citizenship. Perhaps there is something in the partnership agreement. Sit down with a business attorney in your area (Not in Africa but TX).
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