It isn’t clear if SOE debt should be considered public or private debt. On the one hand, these are often publicly traded companies, in the other hand everyone assumes their debt is implicitly guaranteed by the government. Localities will often load up local SOEs with debt when they need to do something for public interest, like build a subway or road. So China’s public debt situation is really murky.
Debt can only be debt if you believe there exists profits. There are companies that buy and sell off each other to produce "income". A lot of the numbers are inflated or completely cooked.