GitHub provides an audit log to Organization owners. You can use this to review the users that have been recently invited.
Note: Official documentation is located here.
Revewing the Audit Log
- Navigate to Settings
- Open the Audit Log
- Search for user invites
- Search for
action:org.invite_member
- Search for
- Review the emails that have been invited for any inconsistencies
- The log can also be used to find when a certain user was invited