World of House of Spiders Identity Stories: Rashomon Effect
This thought came to me while trying to figure out the timeline's seemingly contradictory elements and reading others theories and refutations of what happened.
Ryūnosuke Akutagawa, the author of Hell Screen, had another literary work called "In a Grove" from 1922. The major theme of this work is the subjectivity of truth. In that story there are multiple, contradictory accounts of a murder that occurred where even the account by the victim and confessing murderer is considered unreliable. Unlike Hell Screen which is told through only one unreliable narrator, In a Grove is told through seven unreliable narrators.
Objective reality in that story is always rewritten by each witness to suit their worldview and own perceptions of what happened and I believe we are witnessing such an effect right now in the House of Spiders story.
If this is true and such contradictions are intended, this would mean that while Nursefathers Rodya and Outis as well as Thumb Apprentice Heathcliff's accounts of the House may shed more details, it's far more likely they will remain just as contradictory as the others. Like the book which had no true, definitive account of the events of the murder, the world of the House of Spiders will have no true definitive account of its timeline.
TL:DR:
The World of the House of Spiders will forever remain a mystery because KJH wills it in the name of art.
Still, it is fun to play detective trying to figure out what really went down in that world. If the last three accounts doesn't help to clear things up, we can play this Cluedo for a good long while.