I have run into two cases where books contain chapters on unnamed Biblical characters lack Factbook entries where similar character sometimes with lesser roles do have Factbook entries:
- Wise woman of Beth Abel Beth Maacah who appears as a topic but not a person
- Israelite slave girl serving Naaman's wife
Branch, Robin Gallaher. Jeroboam’s Wife: The Enduring Contributions of the Old Testament’s Least-Known Women. Grand Rapids, MI: Baker Academic, 2010. devotes entire chapters to both of these