Nice use of logic
This is a solid example of how form can help determine date. One needs to review the underlying data to see if the argument is persuasive but for most of us simply knowing the argument exists and could be researched is sufficient.
The Lexham Bible Dictionary
after Joshua and the Israelites fought and defeated a coalition of kings in Canaan comprising forces from Jerusalem, Hebron, Jarmuth, Lachish, and Eglon. The king of Eglon was named Debir (Josh 10:3). The city had been called Kiriath Sepher, or “city of the scroll,” and was also known as