Hi,
Could you create custom contact fields for the attendee 'owners', upload the data and use the custom contact fields as the from name instead?
Otherwise, create a copy of the email for each 'owner', rather than resend the same that should prevent any caching issues. It also give you a better history if you need to look back to see which email someone was sent.
Kind regards
Stu
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Stuart Harley [Designation]
Event Tech
Schroder Investment Management Limited
United Kingdom
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