Hi dear,
1. It doesn’t matter because YouTube is not a mainstream platform in China and is barely used by our clients mostly of whom are Chinese.
2. 100audio has three different cooperation modes for different exclusivity, including non-exclusive, China-Exclusive and Exclusive.
We are not sure about Audiam but we offer you several suggestions.
If Audiam has exclusive copright of your tracks in Europe, then you could choose 100audio’s non-exclusive and China-Exclusive. But if they have the global exclusive of your works, then you might have to choose between 100audio and Audiam. But if there is no copyright thing between your works and Audiam, you then are warmly welcomed to be our authors in any cooperation mode you prefer.
You could also refer to this topic for more detailed introductions. https://100audio.com/en/topic/780255/
Hope that helps.