Hello there,
I do have experience working with Google Sheet API and have just checked the SproutVideo API for creating user login. So, I can make a php script that will run on your server with a cron job which will check for any new row added to Google Sheet, and it will add new user login to SrpoutVideo via API.
Let's discuss and I can deliver this in 2 days after we confirm the project.
Ping me when you get time to discuss further.
Regards, Devin.