Editable Text box underneath external Transcript Request form fields

I would like to request an editable text box so that Registrars can add a few lines of text instructions to alumni and former students requesting transcripts.  We can't send unencrypted transcripts per FERPA (without explicit student permission), but some institutions, such as the California Board of Behavioral Sciences, won't accept encrypted transcripts.  We end up having to go back to the student, ask them to submit a new request with instructions (to us) to send the transcript unencrypted, then we delete the old request, and fulfill the updated one.  Allowing us to provide a few lines of instruction would reduce this back and forth.     Hope this makes sense.  Thank you!