You're not being serious, right? The availability of petroleum-based fuels and lubricants was critical center of gravity for the Nazis to have prosecuted the war. If in fact Standard Oil did not do everything they could to stop the Nazis from using their facilities and products then they committed the most serious of treasons.
How many deaths would they have facilitated to have preserved their corporate assets if that was the case?
As a practical matter, the only thing Standard Oil could have done was to sabotage its facilities. The Germans would then have simply shot everyone involved, repaired the damage, and restored production.
Trading with the Enemy: the Nazi-American Money Plot 1933-1949, by Charles Higham. The Strageic Bombing Command has been accused of deliberately avoiding bombinb Auschwitz. Considering the FDR Administration's attitude toward Jews, and that the facts about the death factories had not generally been revealed in the press, the available evidence doesn't support an assertion that that this omission was due to concern for the death camp inmates.
The people on the ground in Ploesti weren’t taking orders from Standard Oil in the USA in 1943-44. Doing so would have gotten them shot.
What could they have done, precisely?
Ordered their Swiss subsidiary to blow the place up? Would their Swiss subsidiary have been able to do so? Would they have acted, at all -- given that they were governed by Swiss law? And their Romanian employees were subject to the German military.
The simple fact of the matter is that Standard Oil headquarters may have been rendered powerless by events. Any orders they might've issued to their Swiss subsidiary weren't necessarily going to be followed.