Allow User fields in CoPilot

I have been creating some great emails via Co-Pilot, but our Legal Department requires a specific signature from our CSMs for external emails.  It would be great if in the Power List creation, I was able to grab User fields specific to account owners, or CSMs.  I can do cross object lookups via SFDC email templates, but am running into limitations in CoPilot.  I can create fields on the Customer Info object for CSM phone number and CSM title that are formulas from the user object, but with SFDC audits I would prefer not to create fields for the sake of putting a signature in an email.  Any help is appreciated!