China came late in the picture after Pakistan illegally gifted a part of Kashmir(Aksai Chin) to China(Pakistanis need to ask why didnt they ask for peoples wishes this time,lol).
But i was talking about the time just after the conflict.According to U.N. resolutions Pakistan must have withdrawn all its forces from Azad Kashmir,after that India would have deployed minimom forces required to maintain peace in all Kashmir(i.e. IOK and Azad Kashmir both) and then a referendum would have taken place under the supervision of these forces.
But as expected Pakistan failed to meet the above criterias and referendum didnt took place.
Now after so many years we dont have any moral obligations to hold referundum especially after the fact that Pakistan has actively supported Terrorists to harm India