Couldn't find it for this theme, but you can go to the bottom and switch to the default theme. There is a 'mark all content as read' near the bottom right.
This is just a guess, but every slot on the inventory corresponds to a child widget (0-27). Try using the widget debugger and see if you can figure it out.
When I do tutorial island manually, I try to rush through everything as fast as possible; like dialogues, spam clicking shit, esc menu closing etc. Maybe rushing it or not spending time in the dialogues raises a red flag. Doubt it though.