Considering the debt ceiling in the US is dangerously close to being breached, I don't think the Chinese will want to peg their currency to the US dollar for much longer and might start to unpeg it from the dollar and other currencies in the near future, particularly now that their economy is in a fairly strong position to do so. Not only that, but they do have a significant presence in Africa by providing funds for infrastructure such as roads and working to help develop some industries, so it really wouldn't be too much of a stretch for any African countries with significant oil fields that the Chinese are involved with to directly trade oil for the yuan without needing to get the US dollar involved in any way, shape or form, particularly if they are not part of OPEC or decide to break away from them if the value of the US dollar tanks due to the debt ceiling being breached. After all, motor vehicle use in China is on the rise due to their burgeoning middle-class and a decent deal for relatively cheap oil in exchange for industrial and infrastructure funding and development would be a good case of scratch-my-back-and-I'll-scratch-yours.