Invasion Graphic Novel Problem

I was reading the Graphic Novel, The Fall of Reach:Invasion and I noticed a change with the story. I’m not saying this is bad in fact I like what Brain Reed did. Still it’s a change and I’m curious about it. Sure Bootcamp, Covenant, and Invasion have little changes in them(Ones that don’t effect the story that much), just this change is one that changes the story a little more.

The change is with First Strike and The Fall of Reach: Invasion.
The Problem begins in The third comic or Chapter of Invasion when Red Team and Blue team split up.
Blue teams(Master Chief’s Team) part is the same, yet Red Teams(Fred’s Team) is changed a little bit.
It’s similar until Red team Meet Charlie Campany at the Generator. Theres acually a few changes at this point.
1)Red Team keep contact with Cortana(They don’t in First Strike)
2)Charlie Company Marine runs away(They don’t in First Strike)
3)All of Red Team fight convant waves at the generator(Fred, Kelly, and Joshua are not there during that in First Strike)

I know that this the Graphic adaption to The Fall of Reach, but still if it was gonna go on to events told in First Strike then maybe it could of shown Charlie company Staying, Fred, Kelly, and Joshua leaving in banshees. The first point(staying in contact with cortana) can be a little bent as it still works as they still lose contact with the Pillar of Autumn.