Overwatch 2 Cosmic Crisis - Call Of The Ravager (Expert Difficulty) - guide/info in description

It's not the full game, but the biggest part of it (I had to re-start recording because I forgot to mute my background music, sorry).

To qualify for finishing this quest, you have to be "the chosen" player of the game. This happens randomly, so every game you have a one in four chance to be the one.
If you are unsure when it is "your turn" to go traitor, there is a PURPLE EDGE EFFECT on your screen with some dialogue from the alien between the first task (extinguishing fires OR cleaning up snow around the space ship) and seeing the alien for the first time (the video sequence after you encountered your first "landing"/dropped mobs on your way out of the first map area).
You can see that same effect with the dialogue telling you to jump into the maw later in the mission again (in this video it's starting at 0:40 m, for reference).

IF it is your turn you can (have to, to finish this quest) jump into the alien's teeth hole (middle of the Antarctica map CP) AFTER EITHER picking up all three keycards OR destroying three beacons and unlocking the room with the batteries.

From there you go and try to kill your former team members, which naturally is easier the harder the game difficulty is, making it a TERRIBLE design for those who "just want to finish high difficulties", which from my experience are most players in PVE.

Before trying "expert" difficulty, I had spent HOURS waiting for my turn on "hard" and when I finally got it as Moira, I was annihilated by an organized (probably premade) group consisting of Roadhog, Soldier: 76 and Mei.

Because of that "PVE/PVP-mishmash" I consider this the worst PVE event ever and hate the developers for it.
They have once again proven to be completely out of touch with the games' community, and after the "canceling pve progressive mode" dilemma this is a spit to the face of loyal Overwatch players still interested in PVE somehow.