Google Product Forums
Re: how to add a second youtube channel to existing adsense account
Apr 5, 2012 9:09 PM
Posted in group:
AdSense in English
Partner sites, e.g. YouTube :
The only way to link AdSense is through the monetization settings page of your YouTube channel:
If you don't have that option in one of your YouTube accounts, you'll have to wait for YouTube to offer you the option to monetize again.