Mr. Sunao Matsuo, a former resident of Hashima Island

I have not seen or heard anything about children being mobilized. It must be an exaggeration.

"He was born on Hashima Island in 1927. He has five siblings, comprising of two older sisters and two older brothers. He still vividly remembers the games he played as a child.
He attended elementary and junior high school on Hashima Island and entered an agricultural high school in Isahaya, Nagasaki Prefecture. Then the war ended while he was a student. His parents were working in water supply work on Hashima Island.
The year after the war ended, he returned to Hashima Island and worked outside the mine in a materials-related job and continued to work on Hashima Island until the mine closed down. "