For invitation emails, as we work a lot with international participants who will need an invitation letter for VISA purposes, we just create a certificate with the participant details and the letterhead of the hosting organization, and a link to this certificate is inserted in the registration confirmation whenever they register. This way the PDF includes some critical information like full name, passport number, etc.
I guess the same can be done prior to the registration using only the contact name on the certificate and include the link on the invitation email.
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Jorge Pratas
Conference Manager
World Sports - United States
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