What is the erro you get when the smart TV fails to connect to the AP? is there any authentication enabled for the guest SSID?
Adding enry in the whitelist (IP's or URL's) will bypass the traffic to these IP's and URL's without guest access authentication. This will not bypass the guest user authentication.
Normally in smartphones CNA detects the guest network and automatically redirect the client to the login splash page. This is a client behaviour. I think the issue might be the automatic redirection is not happening in the TV. Can you try opening the browser on the TV manually and connect ?