No. If there's an industry S&P has a conflict of interest with, it's bankers. Derivatives, how Wall Street mostly trades commodities, don't care what their underlying asset is denominated in.
I believe your question arises from what I refer to as the petrodollar fallacy. The U.S. dollar is used, globally, because Americans buy lots of stuff. Exporters who sell to Americans naturally end up with U.S. dollars. They could sell those dollars for their own currency, or they could invest them in U.S. dollar denominated assets. (Or they could hold them to further buy stuff from other people.) Our deep, liquid and largely politically indifferent financial markets, huge base of consumers and lack of capital controls underwrite the U.S. dollar's global popularity [1].
Given the United States is, again, a major oil producer, what other people trade their oil in is largely irrelevant to American financial interests. Would certain 3-letter agencies prefer Iran have to sell for dollars? Sure. Is that of even the most vanishing concern to Wall Street? No.
[1] Historically, the U.S. dollar supplanted the pound sterling after World War II. The U.S. Treasury, through Harry Dexter White, hard coded the dollar into the Bretton Woods system [a]. He could do this because the United States was the only industrialized power untouched by the war. (We also had a nuclear monopoly.) Either way, nothing to do with oil.