I'm pretty sure inviting Taiwan to such an alliance would quickly trigger WW3
Why would the PRC start a war they know they can't win? If they thought they could win, why haven't they done something about it yet?
Also, better to fight this now than in some potential future where the PRC is stronger.
Not that I'm an expert on these things, but I've read that a nuclear (or even huge conventional) bombing of the Three Gorges Dam would create such a massive flood that it would kill hundreds of millions and wreck the Chinese economy for decades. So it's probably smart for China to never be involved in a World War.
Granted, America would have to be super desperate to even consider doing something like that, but Russia might be willing if losing a China v. Russia WW3.