Not quite understanding how GDrive server side copy works

[Animosity022]

Quite a number posts on 404s as you need to setup the proper permissions:

Google team drive server side copy

I think that is about how to set up a personal API key. That is not relevant to this problem. Any API key from any account can be used as long as it is authorized to access the data. What is important in this situation is that the Teamdrive user who has write-access to destination also has read-access to source. Otherwise there is no way for that user to ask the Google server to copy that data. When you do it via your own PC it does not matter if the different places use different accounts wi…