Is this a corporate instance of Google Sheets or just the regular personal Google Sheets? Did you set it to embed the password when you published the workbook?
You can follow these steps listed here.
You need to install GlobalSign R2 certificate on the Tableau Server. you can download it from here.
Please make sure, Tableau Server can connect to google sheet to get new data. (You can test it by pinging google sheet URL from command prompt)
Thank you for providing help Krunal, I am currently putting the above steps in place.