The source for student metadata is a collection of "custom student metadata", uploaded through the CSV file on the admin panel, and the data received from your IT team. Editing the student_metadata.csv file on the admin panel will only affect the custom student metadata that was previously imported through the student_metadata.csv, not the information within the Student Metadata SFTP Import. To manually upload custom student metadata, please review the article, Optional (Admins): Manual Upload of Student Metadata.
IT article: Optional Admins IT Integrations