Watched it at 2X speed? I have no words, my heart is crushed. The disrespect to my current favourite show!
This show is as much about the characters, corporate satire, the politics of power, depression, fanaticism, as it is about straight up plot. If you rewatch from that point of view, it will make more sense.
spoiler
You have to remember that the innies know very few people. They spend their entire waking existence with their team, so if someone is not behaving as themselves it will be noticeable. Irv was suspicious of the gardener story, and then various other interactions he had with Helly seemed off. Her tone of voice, he face, everything was slightly off. Mark didn’t notice because he had rose coloured glasses on, and Dylan never went ‘overtime’ because he was holding the switches. So Irv was the one who was most sensitive to the changes in Helly. He felt he had nothing to loose, since Burt wasn’t at Lumon anymore, so took the risk for the sake of Helly and the team.
Can’t sleep. That’s all.