Let me tell you the truth.
For Russia, the role of SOC is to ensure that Central Asia and China will not turn to the West.
For China, SOC is a platform to avoid antagonism with Russia while allowing China to enter Central Asia.
In fact, India is not a necessary member, but Russia is afraid that China will become the leader of SOC, so they brought India in.
For India, in fact, Russia is their truly reliable ally. India's interests need the veto power of the UN and the support of a truly powerful nuclear arsenal, which the USA cannot give it. So the Indian government will serve Russia in SOC, not the western countries.