I tried the game as well. After playing it, I read the comment. Unlike most people, I successfully turned the circuit breakers back on, but the key still didn't spawn...
Hi! I checked your playthrough and the key did spawn. I saw it on your gameplay :) for the sake of not spoiling the game I'm not going to tell you where it is but you definitely missed it in one of the bathrooms.
Thanks for playing, and making a video on the game!!
