As noted in a similar question ( How to get current user profile information in the YouTube 3 data API), there may be a difference between the youtube user name (found in youtube.com/user/{the username}) and the name of the channel. The channel header can be obtained through the channel / list resource, however this channel header may not coincide with the name of the user who owns this channel. The problem here is that when the username is unique, the channel name may not be, and this causes a lot of confusion within our application (since we do not have the ability to distinguish between user accounts).
Is there a way in V3 data API to get username?
It displays the display name on the screen under channel.snippet.title