Katanga, the breakaway nation that existed in what is now the DRC from 1960 to 1963, is a bit of an oddity. The independence of the region was essentially sponsored by the Belgian mining company that operated in the area, and it had a sizable White minority, but unlike Rhodesia and South Africa, it embraced majority rule; it even took up nationalist rhetoric linking itself to some pre-colonial kingdoms.
With that said, it was still a nasty place. The Baluba, one of several ethnic groups native to the region, were against independence and led an insurgency against it, and the president had a habit of imprisoning political opponents. Its military was built around a core of Rhodesian and South African mercenaries, and it had no qualms with working alongside Ian Smith and other white supremacists in the region.
Ultimately, Katanga failed to gain western support; the left-leaning Lumumba in Congo was ousted by the infamous Mobutu with CIA support in 1961, so Katanga's mineral wealth was no longer threatened by the Soviets.
So, what if Mobutu was killed and Lumumba went hard towards the Soviets, leading to the west semi-officially supporting Katanga? Could it survive its insurgencies and maintain itself without falling into segregationism? Probably not, on both counts, but it's still fun to speculate.