Place it right at the reveal in an edit, after the mistake is shown and before the reaction shot cuts in. Pair it after the It Was At This Moment He Knew button for a caught-in-the-act sequence, then let the next scene carry the fallout without another effect layered underneath.
Über diesen Sound
The clip is Roz's dry, flat voice delivering her watchful warning in a seven-second Monsters, Inc. moment, all gravel and no warmth. It feels funny and faintly accusatory, like getting caught mid-mistake by someone who never blinks and has already filed the paperwork in her head.