I think it is important to distinguish between morals-as-statements and morals-as-actions. All GP is saying is that the actions of the Chinese state, while against western morals (as stated), are permitted by the (in)action of western states. They're not claiming western moral superiority (which would admit such a tu quoque argument as you present), or claiming that western states act morally (which as you point out is demonstrably false). I think you're reading too much into it.
