Try using the Authentication methods endpoint: https://learn.microsoft.com/en-us/graph/api/authentication-list-methods?view=graph-rest-1.0&tabs=http
How to retrieve the MFA status with a Disabled User with Microsoft GraphAPI
We are using PowerShell to query a group of users.
$user = Get-MgReportCredentialUserRegistrationDetail -All | Where-Object -Property UserPrincipalName -eq $UPN
It can get us user, which is not a disabled user, AuthMethods. But for Disabled users, we want to log it for audit purpose. This returned us a blank string.