Send Reminders to email addressed based on custom field

Send Reminders to email addressed based on custom field

We have a custom field in Customers that has an internal email address of who should be notified when an account is past due beyond 30 days. Is there a way to use the Reminder function in Books (or possibly in Zoho Flow) to have the reminder email be sent to that address (I only see the option to pick users for all customers at once). Each customer will be different.