The AU seems likely to be a in better spot, in part because it is built on regional "pillars" and a lot of separate organizations, so even if the AU itself for some reason were to fail, it is already having massive impact. E.g. ECOWAS covers 15 countries and ~350 million in West Africa. SADC covers 16 states in Southern Africa etc. COMESA acts as a superset of SADC and EAC, providing a free trade area covering 400m+ people in Southern and Eastern Africa, and so on.
A number of monetary unions have started coalescing the currencies of he continent, as well, so even if the progress towards a single African currency were to fail, that too is still having an impact.