This is an excellent point. You can't prove much. If the person or the AI closing the account knows enough to make a decision, those details can be repeated again.

This is how it's done in the real world. When judges sentence someone, they repeat the charges and the guilty verdict. When parents scold a child, they tell the child why.

I mentioned in my first comment that he can not prove this, and the Wikipedia link explains why he can't (fundamental law rule). I definitely agree that Google should list the reasons for what they did. Ideally there would be a public mechanism where everyone can see the history of violations associated with a developer account.