I noticed the same thing. With the nanomachines MC sees "proof" that his girlfriend is doing "activities" and doesn't have a reaction. Not even a suspect.
What you as the player see is not the same as the MC sees. I can understand the confusion this creates and that is why I am planning to add a true MC pov to a future update. This will allow the player to see what the MC can actually see. I hope this answers your question 😄