First, the Democratic Republic of the Congo is not one of the African countries which are high risk for Group O. The "Congo" they are concerned about is the Republic of the Congo (notice the lack of the "Democratic" prefix). So, suddenly I am able to donate blood.
They do anticipate having a screening test that can detect 100% of group O carrying blood as soon as the FDA approves one that matches their screening methods. The only currently FDA approved group O antibody test does not use the right kind of technology for their screening process.