How different is the arrival/unlocking of Sinon and Leafa in Hollow Fragment when compared to Infinity Moment?

When I played Sword Art Online: Infinity Moment, Leafa and Sinon where nowhere to be seen in Floor 76 and no indication was given to how or when they will become available. On Sword Art Online: Hollow Fragment, both of them are unlocked from the start of the game after finishing the Hollow Area Tutorial.

How different is the arrival/unlocking of Sinon and Leafa on Infinity Moment when compared to Hollow Fragment? How were you able to unlock them in the original game?

The "Do you want to think back on what happened in Aincrad?" cutscene shows that Leafa

was found in a forest

and Sinon

fell from the sky in floor 76

But that raises more questions like

In what floor was Leafa originally found

and

From what floor did Sinon fell down in Infinity Moment

According to the Wiki

After the defeat of the Ghastlygaze, the 76th Floor Boss, Kirito met Leafa, who turned out to be his younger adoptive sister/cousin. She told Kirito that some kind of error had sent her here while she was playing ALfheim Online. Right after that, Kirito met Sinon, who mysteriously fell from the sky of Aincrad and suffered from memory loss.

Source: Story (5th Paragraph)

Since after you beat a Boss you then have access to the next Floor Leafa and Sinon are met on either Floors 76 or 77. As i haven't played Hollow Fragment in a long time (and currently working in the Hollow Area in my new game on PC) so i can't say with 100% if Floor 77 is a forest or has a forest area however Floor 76 does have one to the right of you as you enter the second area (where you find the group of players talking about a strong monster in a cave up ahead)

as for Sinon, since the scene of Kirito catching her as she falls out the sky is shown that Kirito is in a town and not in the field (you see a street, lights and some houses in the background) this could be (lore wise) either town on Floors 76 or 77, though game play wise since you can only walk around in Arc Sophia this is the only town where it would be possible (though given the artwork one can assume lore wins here and the developers of the game just couldn't have towns for every floor for some reason)