Hello Kim,
Just to clarify your question. The administrator's email address you are referring to is if someone registers on "behalf of"? If so, you will need access to the Address Book > Admin > Contact > Address Book to update the email address.
I believe the Administrator Registration Confirmation email can't be sent manually but maybe using Test Send you can manually add a custom email and not sure if that will send to the person on not.
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James Rose | Senior Web Developer and Platform/Product Manager
Digital Infrastructure
Office of University Development | University of Michigan
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