SharePoint Administrator should have Full control over Video Portal since it is a part of SharePoint. Currently only Global Admins can manage Video Portal so its basically bug that SharePoint Admins cant manage Video Portals.
Ami Brandes commented
After opening a case in Office 365 support, it was investigated and the response I received was that it is still impossible to share a video with external users. It is still in development. The feature does appear as though it's available in the Video portal (it is possible to restrict or permit access to certain users who can be allowed to view videos in a specific channel), so seemingly it's possible to choose "everyone" or even "external users" if you wish to enable an external user the ability to play back a video you posted in a channel. But these settings do not work and Microsoft is unable to tell when these access controls will indeed become active. So sadly I need to continue to use YouTube instead of Office 365 in order to share our organizational videos with people who are collaborating in our projects but are external to the organization....
Dick Sawczuk commented
Is it possible to hide the Embed and EMail links when playing videos
Jitendra Singh commented
Here is the Microsoft Case number 616102091815222