I linked my iPad and iPhone with the TCL YouTube app using the “Link with TV code” feature. I can see that it’s linked. But when I try to start a video after I leave YouTube, it won’t start until I re-link my device again. Not sure if it’s a bug with Roku or with the YouTube app on the Roku.
For more information about that channel's features and functionality, you'll want to contact Youtube support directly to inquire further. Many channels on Roku are developed and maintained by the channel provider themselves.