No, the game I was talking about is IF, as in Interactive Fiction, what text adventures are called now.
Without giving away the major plot twist of the game I'm thinking of, I can assure it has nothing to do with Lifeline.
Edit: found it! It's called Fail-Safe, and if you ever intend to play it, please don't read spoilers. The game is so short, almost a single "scene", that spoilers will really ruin it: https://ifdb.tads.org/viewgame?id=c6x835i6o9zqfc59
Without giving away the major plot twist of the game I'm thinking of, I can assure it has nothing to do with Lifeline.
Edit: found it! It's called Fail-Safe, and if you ever intend to play it, please don't read spoilers. The game is so short, almost a single "scene", that spoilers will really ruin it: https://ifdb.tads.org/viewgame?id=c6x835i6o9zqfc59