ADFDI worksheet login to be authenticated via IAM domain rather than regular sign on page

Summary:

ADFDI worksheet login to be authenticated via IAM domain rather than regular sign on page

Content (please ensure you mask any confidential information):

Hi,
In our system, all supplier portal users are setup to be authenticated via the IAM domain with MFA enabled. Once a supplier logs into the application and downloads an ADFDI worksheet (such as Acknowledge Schedules using Spreadsheet), current ADFDI login page is regular SSO/basic auth page with username and password.

However, client requirement is that the sign in page during ADFDI login must also be authenticated via IAM domain only. Kindly confirm if this is feasible and need inputs on its configuration if it is possible.