In real life, China was certainly non-aligned thanks to the KMT. However, by the end of the war they were recognized as a major Allied power and were still on good terms with the USA (although not by the civil war)

So when the United Front breaks up and if Nationalist China wins the civil war, can it join the Allies? I mean, if non-aligned Greece and Poland can be part of the faction, there's no reason China can't either.

Maybe an event where the Allies recognize China as one of the "Big Four" and invite them to join their faction?