Ability to send/block resource alerts to a specific work structure ie business unit

Summary

Need to stop resource alert for new learnign assignment going to a certain population

Content

We are trying to configure the New Learning Assignment resource alert in a particular way so that the whole organisation gets the notification in the worklist but also only users who aren't in our food business receive the notification by email. The reason for this is we only have personal email for our food colleagues. Please see the image below for the standard setup.

Hoping someone can help with an expression that would stop the mail going out to users in a particular division or multiple business units