The Intro

For right now we don't know much about the how or why of what makes the EVENT that makes the CJM-Verse happens.
Here's What we do know:

• The EVENT has stopped time in nearly every other reality, or at least every reality that had people abducted.
• People in the CJM-Verse no longer age
• Alongside people, certain landmarks, cities, and infrastructure were transported to the CJM Verse.
• Resources were placed in the world, but only a little bit more than just enough.

I assume there would be a brief scene depicting the creation of the CJM-Verse, Or maybe it just starts with our Heros in an empty field (I imagine it as a place with black clouds hued a kind of purple-blue, with purple barren soil and dead trees) Either way were not sure how to start the narrative. There was talk of a robed figure issuing a challenge SAO stlye, but since nearly everyone involved in the EVENT spends a year creating a new society instead of trying to get home, that seems a little less credible now.
Either way, after the introduction scene that leaves the Heros alone in a field.

First Scene

Effectively from here we want 2 things to happen
1: We want the Heros to make their way to Rollinsberg, That's where most of the action of the prologue will be taking place.
2: We want the Heros to meet their First Summons.
With that in mind, the heroes may have been told that their first summons is nearby to pick up the pace. They could even have been told they need to find Rollinsberg.
I can see this going a few ways:
The heroes go out looking for their First summons.
The heroes decide they need to find food, water, and make a shelter and go full bear grills.
The heroes decide they need to find civilization and head off to look for somewhere safe.

After that, I can see 2 things happening almost regardless of their choice.
The heroes happen upon their First Summons, I imagine they do so individually but maybe they do so as a group.
The heroes find a Paved Blacktop Road and begin to follow it to civilization (Rollinsberg)

Rolling into Rollensberg (It's not called that yet)

At this point in the story the Heros have arrived in Rollinsberg. They may recount everything they know thus far and try to come up with a plan.
However, we now want the Heros to split up, to make writing the plot a little easier. That doesn't mean they can't pair up right now or regroup later in the plot, but for right now they split the party. Assuming they're safe in a town.
There are a few things the Heros may notice about Rollinsberg as they traverse it:
Citizens of the origonal town (I guess Blade runner LA) Still populate the area but very few of them where taken by the EVENT (Like a few thousand but this was a mega city so, it's emtier than their used too)
The state of these citizens could be, In shock
Or may have accepted the situaion and:

Are wondering if enough people made it to keep the city runing.

Wonder if everyone not here is dead,

Wonder if their dead and this is the after life

Wonder if this is the rapture

Realize most of the police force is missing and decide to start looting.

Also their will be People running around that the Heros recognize from fiction. SOmething they will already be aware of if they met their first summons.

This is not a list we need to exaust or hit every note on, It's just something to give people Ideas as their writting.
Whatever the case this Breaks up the story into multiple persepctives:
Chris
Jeff
Mike
Rocky
Proluge Tree: Ben
Prologue Tree: Utraman Geed (also possibly unlocking Geed)