Trying to setup the TV Everywhere with Youtube TV as my provider it is timing out at the password screen. I do have multi-factor tied to my google account so I am not sure if that is an issue. Thank you.
Unfortunately we don't support accounts with 2FA enabled at this time 
I am also trying to use an google app password so I don't have to use multifactor and it is still getting timed out at the enter password screen.
Could you please email us [email protected] with a screenshot and the logs from the Log tab and we'll take a look. Using an app password is a good idea!
I tried setting up an app password and then trying to use it in an incognito window to login to nbc.com
Unfortunately it doesn't work. It seems like app passwords only work for Mail, Calendar, regular YouTube, etc.
I did send a email to that address.
Just so if anyone else trying this app password does not work with Youtube TV. You may have luck creating a secondary Gmail account and setting up as a family member and using that login, but all my family members are being used so that wasn't an option for me.