I am not aware of Chinese Universities or any of the rankings that have been mentioned in the question, so my answer will be an incomplete one.That said, MBBS is not about passing in exams: it is about how much clinical and hands-on experience you can get during your clinical postings and internship. Anybody can learn theory; it is the practical and clinical training that actually matter.
Consider these two scenarios:
A brand new medical college with super-awesome infrastructure, centrally air-conditioned classrooms, all possible equipment, amazing faculty, but only fault is that the patient load is meager
A medical college which has been consistently rated to be poor in terms of infrastructure, classroom teaching and equipment, but is attached to a hospital which is thronged by patients.