Allow for Onboarding custom email field to be visible to workflow automator action "send email to"

My goal is to use an Onboarding bundle including a service item to create a new company email address for the new hire.  Using the Workflow Automator, when the service item ticket has been resolved, the action taken would be to send an email to the new hire’s personal email (not company email) by pulling in a  custom text field “personal email address” found in the create a new company email address service item.  The purpose of this would be to inform the new hire how to access their newly created company email account and provide them credentials for logging in.