Thank you, WillowRun 6-3.
You've posted by far the best summary of the state of play for space hazard rules that I've ever seen. Clearly China pushed the tentative envelope with this launch, but 'soft law' has no teeth.
I think there are two more sections to be launched for the Chinese station. It will be interesting to see whether their boosters will likewise decay randomly, or whether China will make some effort to control their demise.