sending email to users with specific brand url using API end point

We are migrating users from one instance of zendesk to another Zendesk as part of project of consolidation of Zendesk instances to enterprise edition that has multiple brand.

We have migrated the users with verified set as True. Now we need to send comms out to user with with specific brand (not exposing all brand url all migrated users) using zendesk API.

We are looking for option that will enable us to send email to migrated users with brand url and request for them to reset their password on new instance.

Having discussed with Zendesk support they recommend there is no API interface for sending email out.

someone recommended on the forum usage of /api/v2/users/{user_id}/password/reset but that does not work now.

We are looking for options similar to password reset on /agent/users/380933125960/security_settings using api call