While I agree that the Reod did not happen at the time of the shattering of Skaai or Aona, I think it is related. My current theory is that the earthquake was caused by the excessive investiture in the cognitive realm, pushing against the physical for a time.
But... my current theory about the Recreance is that was it was directly related to the shattering of Honor. I believe after Honor died, there was a specific impact on the Knights, that caused them to specific choose to give up the bond. I am thinking they knew that without Honor the safeguards of their bond were not in place, and they could do more harm than good.
Perhaps there still could have been an impact toward Sel, bumping up against the investiture, which bumped up against the already strained physical, and causing the earthquake. Interesting to think about.