Secondary domain websites registered on WordPress can not be verified the classic way by downloading a HTML file that needs to be uploaded on your site because you can not do the later. Below you will find the method to verify a website you don’t have access to its source code.
In order to confirm your WordPress blog you need to follow this path:
- In your YouTube account:
Creator Studio -> Channel -> Advanced -> Associated website (where you need to enter your website URL and then click “Add”) -> Verify (on the message that appears below) -> Other methods -> HTML tag
Then you copy that tag which you have to paste in “Google Webmaster Tools” section:
- In your WordPress admin panel (i.e. yourblog.wordpress.com/wp-admin)
Tools -> Available Tools -> Google Webmaster Tools.
After you pasted that, you press Save Changes, then go back on Google’s Webmaster page where you need to click on Verify. It should display a message that your website has been verified. After that, you can add Cards, End screen or Annotations in your YouTube videos that link back to your website.
Side note: from the Google Webmaster page – Search Console – you can as well add for verification multiple websites, as displayed in the video from the link below.
As seen at: Link a WordPress site to your Youtube channel by manuel martel