Hi there, @ptollinger. 

Thank you for reaching back to the Community. To view all users who are using the 2FA is unavailable in QuickBooks. As a workaround, require all users to log in to https://accounts.intuit.com/ and confirm if your profile is already turn on the Two-step verification. If not, you can follow my colleague @MJoy_D steps above on how to turn on the 2FA. 

For more information about 2FA you can follow this article: Turn on or turn off two-step verification. 

To learn more about Verify your account with multi-factor authentication, please refer to this article: Verify your account with multi-factor authentication. 

That's it. Please let me know if you need further assistance with it. I'm just a post away. Have a great day!