I am implementing a passwordless signin experience for local B2C account users with MFA credentials through Azure B2C custom policies. I am using AzureMfaProtocolProvider with a custom attribute stored phone number as an sms MFA option, and OneTimePasswordProtocolProvider with a custom attribute stored email as an email MFA option. When I initiate a login, the first step us username retrieval. The username is used to read the mfa options from AD and then presented to the user as options. Once they select an option, a code is sent and they must successfully validate the code from one of the MFA options to issue a token to the application. This works great, however I noticed that Active Directory does not store and log a "sign in" in the signin logs (https://docs.microsoft.com/en-us/azure/active-directory/reports-monitoring/concept-all-sign-ins). Per the document, MFA challenges should generate a signin log but it seems that MFA challenges with these protocol providers (AzureMfaProtocolProvider/ OneTimePasswordProtocolProvider) are not sufficient.
I am concerned that we will miss inherent Active Directory risk tracking without "sign ins" being generated. I am also operating with a business requirement to see those logs generated for auditing purposes.
As a work around, I am adding a psuedo password to user accounts on creation and then faking a login with the "login-NonInteractive" technical profile, which validates the credentials in AD using OIDC. This successfully generates a signin log but it seems hacky. My question is what is the recommended approach to generate a signin log in Azure AD with a passwordless solution?