Was it ever listed as a provider? Those initial questions you answer on the website when you first activate a device only serve to provide a set of recommended channels/apps that will be automatically installed. I don't believe it does anything to actually validate your provider and activate those channels/apps. As far as I know you still have to do it the first time you launch the channel/app where it will once again ask you for a provider. That's when YoutubeTV should show up if it's appropriate to the particular channel/app.
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