Hello elias ortiz,
Welcome to Microsoft Q&A forum.
Please note that this is a user-to-user support forum. Moderators, contributors including external Microsoft employees cannot directly intervene in Microsoft product features or access back-end systems. Our role is limited to providing technical guidance on reported issues, requests, or ideas. In this case, you should contact Microsoft Support for more information. Or if the organizer profile has a Xbox Profile of its own, you can also consider contacting Xbox Support.
While a child account cannot see the organizer email for privacy and security reason. You can still log into account.microsoft.com/family to see the name of the organizer. It could give you an idea of what the organizer email could be. Also, if you have authorized any action from the child account before, it could still be in your mailbox.
Thank you for your understanding.