Is the Chinese government under any obligation to stop the forced harvesting of organs on prisoners that they started?
Although several human rights complaints have been filed with the UN and other international organizations, China has denied any wrongdoing.
Also, among the area populated with Uyghur Muslims (the ethnic group targeted by the organ harvesting scheme), there is a lot of security and surveillance. It is not easy to send reporters or outsiders into those areas, and impossible for them to infiltrate any surgical centers where the procedures are happening.
China, as an independent nation is not "obliged" to stop doing anything. Although a great deal of international pressure may bring focus to the issue and force China to stop. At the present moment, most international powers seem to want to avoid direct confrontation with China, so the abuse is not likely to stop anytime soon.
Given that china has never acknowledged this practice, I am not sure how they would stop doing what they have not admitted to doing.
It would be like asking if Saudi Arabia is under any obligation to charge the crown prince for Khashoggi.
Why would they be when they have never acknowledged the crow prince or anyone was involved.