Prey (EP)
59 Achievements
40-50h
This Never Happened
You performed an apto-regressive neurotomy on Dahl. Details for this achievement will be revealed once unlocked
12.2%
How to unlock the This Never Happened achievement in Prey - Definitive Guide
Thankfully Dahl is right there so head on down and knock him out with your stun gun! Iwbe will tell you to leave the body there and after a little while he will call you to meet him in the Neuromod Division and the area you are going requires you to unlock it with HACKING II from the security station. Meet with Iwbe and follow his instructions and that's it.
It's spelled out in the video you linked.
You can only do this if you have saved Igwe. See "Adrift" for tips on how to do that. Once Dahl arrives, Igwe will contact you and ask you to meet him in your office. He will ask you to incapacitate Dahl instead of killing him. Once you explore Dahl's shuttle in the Shuttle Bay, you will have to go to Life Support to restore oxygen to the Cargo Bay, or the survivors will die. Dahl will be waiting for you there. Use your Disruptor Stun Gun to knock him out. Alternatively, if you had already fixed the air supply before Dahl's arrival, or if there is no one in Cargo Bay to save, you can find Dahl trying to hack into Alex's safe room in the Arboretum. Knock him out there.
Eventually Igwe will contact you telling you he has taken Dahl's body to the Neuromod Division. Return there and help Igwe perform the apto-regressive nerotomy on Dahl to unlock the achievement.
You can only do this if you have saved Igwe. See "Adrift" for tips on how to do that. Once Dahl arrives, Igwe will contact you and ask you to meet him in your office. He will ask you to incapacitate Dahl instead of killing him. Once you explore Dahl's shuttle in the Shuttle Bay, you will have to go to Life Support to restore oxygen to the Cargo Bay, or the survivors will die. Dahl will be waiting for you there. Use your Disruptor Stun Gun to knock him out. Alternatively, if you had already fixed the air supply before Dahl's arrival, or if there is no one in Cargo Bay to save, you can find Dahl trying to hack into Alex's safe room in the Arboretum. Knock him out there.
Eventually Igwe will contact you telling you he has taken Dahl's body to the Neuromod Division. Return there and help Igwe perform the apto-regressive nerotomy on Dahl to unlock the achievement.