Hi, I was having a hard time playing the Atmospheric Processor 27 mission, trying to kill some eggs in a certain room without being detected.
After sometimes not being able to kill the eggs with flamethrower, and other times being able to kill the eggs without understanding why. I ended up discovering a weird way that guarantees that the eggs actually die with the flamethrower without you being detected.

It's hard to explain, but you need to aim a little further with your flamethrower. If you only target the eggs, the eggs will survive. I took some prints to try to exemplify better.

This first image is when the eggs die: https://imgur.com/a/EE0DuNM

In this image the eggs survive: https://imgur.com/a/cHE8ENs

Note that the cursor in the first image slightly exceeds the line of sight of the flamethrower targeting the eggs. While the second image the cursor is targeting on top of the eggs. I ran the test 5 times in that same room and they all worked. I tried killing other eggs in other rooms in this same mission using this method, and it worked too.

Another image further exceeding the flamethrower's line of sight killing the eggs as well: https://imgur.com/a/6IHhbKu

Anyway, it might not be a big deal for many here, but for me who didn't have a Sniper at the time, it was a victory to go unnoticed through this room. And maybe it will help other players looking for other strategies to go unnoticed by the game's challenges.