An IC in a Chinese territory doesn’t count as a “Chinese unit” for purposes of restricting Chinese reinforcement placement. While China does control the IC, it can’t use it, so it’s not a “unit” as far as China is concerned.
I believe Manchuria would go to Germany if Germany liberates it from the Chinese.
Correct, though actually Germany would be capturing it, not liberating it.
I actually has something like this happen. Russia had been overrun and an italian tank took manchuria. I asked and the territory went to italy.