Hello @Knowledge_gainr,
What PhilipDAth said is correct - it's not supported to specify specific people/sponsors to receive the email within the domain (as any user with an email from the domain will be able to grant access to guests).
However, the following workaround is suggested in this documentation and is recommended:
If an organization requires only specific users to grant access to guests, these specific users will need to have their emails on a isolated domain that is only for these users. Then, you must specify this domain as the "sponsor email domain", which is a domain that contains only these few specific user email addresses.
The below example is provided:
"For example, if the specified domain is meraki.net, any employee with a username@meraki.net email will be able to sponsor the guests. If the administrators want only specific emails to have the authority, then the specified domain has to be a different domain; for example "@merakiguestsponsor.net" with only a few emails on that domain like username@merakiguestsponsor.net that can be specified by guests to grant access to them."
Best,
Feli
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