Either there's a continuity error at the end of SOTF or some of our assumptions are false

I think it's safe to say that the dominant theory on this sub about the conclusion of SOTF is that R-Ka seeks out Vis because O-Vis killed O-Ka, making Vis the only synchronous person and therefore the only one who can stop the Concurrence. But according to the chronology of the book and a few assumptions which I believe are common here, O-Vis kills Ka many hours after R-Ka tells Vis that, as of a few hours ago, he is the only one who can do what needs to be done to stop the Concurrence.

The widely-held assumptions are:

1. Time is synchronized across the three worlds. No Narnia stuff where time passes at different rates between worlds. There's evidence for this in:
   1. the fact that Caeror says he's been waiting 7 years for Veridius to successfully send another student, the same amount of time that has passed since his death in Res
   2. the pains from injuries that leak across to Vis' other selves at roughly the same time since Vis ran the Labyrinth
   3. his involuntary mutterings of the Vetusian stuff from when he and Aequa were in the ruins occur roughly the same amount of time after Vis ran the Labyrinth
   4. It's dawn or just after in both Obiteum and Res when each Vis exits the Labyrinth ruin. In Luceum we can assume it's daylight at the Tempeall Albios since he describes the scenery
2. Time zones are not a significant factor. If it's currently dawn in Caten, then it is also roughly dawn in Caer Aras and no later than mid-morning in Qabr.
   1. The east-west distance between eastern Nyripk (in Obiteum), Deditia (in Res), and Tensia (in Luceum) are about 3000 miles according to the map. On Earth at low-mid latitudes that would be roughly 3 hours time difference, but as you'll see below, even 6 hours can't account for the discontinuity between events at the end of SOTF.
   2. It's possible that this planet is much smaller than Earth, making the time zones thinner and the time differences larger, but without evidence to the contrary I think we should assume it's roughly Earth-sized. Certainly in Deditia and Tensia, times should be very close because they are pretty much due North/South of each other.
3. At the moment O-Vis touches the crook and sees through his other selves' eyes, he is seeing what they are seeing at that exact same moment, not past or future events. We can use this point to plot a timeline in each world
4. The death of O-Ka is the event that occurred only a few hours before R-Ka and Vis met, which led him decide to negotiate with Vis instead of killing him, now that Vis is the only known person who can stop the Concurrence (presumably because he's the only synchronous person).

At the moment O-Vis touches the crook and briefly opens a window to his other two selves,

• L-Vis is tied up on horseback approaching Caer Aras and hearing sounds of battle. In that Luceum chapter, he mentions hearing the sounds of the siege long before they arrive there, and that night falls sometime between first hearing the sounds of the siege and arriving, so safe to say it was roughly dusk at Caer Aras at that moment. King Ronan is executed at dawn and then big showdown happens. He then passes out for 4 days so when he has his brief chat with Ruarc after and learns that one of his counterparts has made a terrible mistake, it's ambiguous whether Ruarc is referring to killing O-Ka or joining with R-Ka. I'm sure we all have theories but I'll leave that for another post.
• R-Vis is watching THE EVENT outside of the prison in Caten, and this also takes place at dusk. A few hours later (call it roughly midnight), after the prison sequence and convincing Eidhin to join him, they encounter Ka's iunctus and find out that, as of a few hours ago, Vis is now the only person who can trigger a Cataclysm to prevent a worse fate. We know it's still the middle of the night because it takes an hour for the iunctus to guide them safely to the docks, and then several more hours sailing to Agerus before dawn breaks as they are walking through the cemetery to the Necropolis.

However, O-Vis does not kill O-Ka until almost a full day after grabbing the crook and seeing the visions!

• After the visions, Vis leaves the chamber with the crook and flail, accidentally explodes a wall and knocks himself out for an indeterminate amount of time, but let's be conservative and say it was just a few moments.
• He then spends about an hour practicing with his new weapons
• It is night when he leaves Qabr. This makes sense, assuming it was dusk at the moment he saw the visions of his other selves. What doesn't make sense is . . .
• It's the next afternoon when he enters Duat and starts wreaking havoc, and at least a few more hours after that until he stabs Ka. This is at least twelve hours after R-Ka basically tells Vis that he's the only synchronous person now.

So as I see it, either we have a continuity error or one of our assumptions is false. At this point my intuition is that the false assumption is #3, that the visions are what the other Visses are experiencing at that exact moment. We know so little about these weapons, the lore and magic system, we're mostly basing the assumption on the fact that it's around dusk in all 3 locations, as well as Vis's intuition:

What did I just see? It felt like me. Not like a memory I never had, but like something I was genuinely experiencing, right then.

All this talk of synchronism makes it sound natural that the visions would be time-synchronized. But there's no reason that the visions couldn't be highlights from the past 24 hours or premonitions for the next. In fact, the next line after the visions indicates that it may be showing the future:

My left arm screams. It is metal. It is gone.

At that moment, L-Vis has not yet had his silver arm attached (either with a harness or by imbuing) and R-Vis is not using his triangle mesh arm in front of Decimus. The feeling of a metal arm, at least, must be a premonition of Deaglan becoming Silverhand.

And if it is showing the near future (roughly 24 hours later) then that fixes the continuity error, as O-Vis would then kill O-Ka a few hours before R-Vis and R-Ka meet.

What do you think? Did I miss anything? Perhaps some other event caused R-Ka to change course and help Vis instead of trying to kill him?