Hello Sree S V,
I tried to send meeting invite to the external email(gmail), and I was able to get the response when the attendee accepted the invite.
I am able to get the accepted response via outlook email and also via Graph API. Using the below endpoint, I am able to see the response of the external(gmail) attendee.
GET https://graph.microsoft.com/v1.0/me/events/{event-id}
Please refer the below screenshots:
Graph API response for attendees:
Hope this helps.
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