Sending reset password notification to additional mail inbox


TLDR; How can we set up keycloak to send password reset message to an extra mail inbox?

We have all our users managed in on premise MS Active Directory and email inboxes in Exchange. There are users with inboxes in Exchange and externals without. Our Keycloak synchronises with AD and runs as a OpenID provider for other applications. So everyone can change their password in Keycloak. Now we have the problem, when a password expires users can use the reset-password- function in Keycloak, but receive their message in their company inbox in exchange, where the password expired. Until now, we had small scripts dealing with this. In AD there is a attribute “otherMail” which we only used to also send this restore option.
We did sync this attribute with keycloak mappers. But now, how can we send the reset message to this inbox?
I was thinking about a plugin waiting for a reset event triggered sending this extra Message to the user but just wanted to ask if there is a better way. Users are not able to change this address.

Anyone with an idea?
Thank you,