’had almost forgotten’

Hello, everyone,

Mrs. Klein told her first graders to draw a picture of something to be thankful for. She thought that most of the class would draw turkeys or Thanksgiving tables. But Douglas drew something different.

Douglas was a boy who usually spent time alone and stayed around her while his classmates went outside together during break time. What the boy drew was a hand. But whose hand? His image immediately attracted the other students’ interest.

So, everyone rushed to talk about whose hand it was. “It must be the hand of God that brings us food,” said one student. “A farmer’s,” said a second student, “because they raise the turkeys.” “It looks more like a police officer’s,” added another, “they protect us.”

The class was so responsive that Mrs. Klein had almost forgotten about Douglas. After she had the others at work on another project, she asked Douglas whose hand it was. He answered softly, “It’s yours. Thank you, Mrs. Klein.”

I guess the author’s intention to have used “past perfect” in the underlined part would be one of the following two;

1) To express the time line from (A) the earlier past until (B) the time that the class was so responsive, if I interpret “so ~ that ~ ” clause to be “to such a degree that”, or

2) To express the time line from (B) the time that the class was so responsive (C) the later past, if I interpret “so ~ that ~ ” clause to be “cause and result”

I would appreciate if you guide which is better one, while I’m inclined to 1).

* source; https://www.rd.com/article/thanksgiving-story/