Place it on the reaction beat right after the visual payoff, not under dialogue, then either end the edit there or follow it with the Roblox Oof for a second, smaller hit before the next scene or replay begins.
About this sound
This is a very short clip of many people whistling together in the Argentine colectivo style, a loud descending chiflido lasting just over a second. It feels teasing and dismissive, like a crowd instantly voting no, which makes a bad play or awkward moment sound even more unanimous and funny.