It is as useful to say what the published record lacks as to say what it contains, and for this type it is more useful.
The scholarship holds the structure in detail: the notation, the instruments, the count, the sequences, the institution of the diviner and much of the verse itself in transcription and translation. What it does not hold, and what no book could hold, is the working practice. Which of many possible verses a diviner selects for the person in front of them, on what grounds, and what follows from the selection, is not written down anywhere because it is not the kind of thing that can be. It is judgement, acquired over years and exercised in a relationship.
There is a second and blunter absence. Much of the interpretive material is simply not published on purpose, withheld by practitioners including those who are also scholars, because it is conferred through initiation rather than circulated. That is a decision by the people whose tradition it is.
The atlas describes Irete Meji as one of the sixteen principal figures, records that a body of verse stands under it, and names the scholarship that has documented the system. It does not fill either absence, because the first cannot be filled by writing and the second should not be.