Even though China has made a mess of these 'negotiations' if you can even call them that, the maesters (scholars/doctors/historians/intellectuals) of the Northern Watch conclude that China does indeed have the better claim to it. However Tibet is far more sketchy.
The Northern Watch so proposes this: China gets Sinkiang but allows any 'Turkish' citizens to leave for Turan, and they promise not to build any military improvements (bases or forts) in the province, and they give up claims to Tibet. Does this sound fair to everyone? (CHRISTOS accept this as you have alienated the entire world on this. You accept this, you can pursue war later if you wish.)