The provision in the Code of Canon Law for excommunication, latae sententiae, of bishops who consecrate others bishop without papal mmandate, and those so consecrated, was actually added to the 1917 Code by Pius XII specifically in view of the "Patriotic" Church and its unauthorized episcopal consecations. Of course in the West it was most famously invoked with regard to Archbishop Lefebvre and the four SSPX members he consecrated without papal authorization in 1988. I doubt if the technical arguments advanced by Abp Lefebvre against the excommunication being effective (necessity, grave fear, etc.), whatever one might think of them in that case, could be thought to apply in the Chinese situation.
Thanks!