Place this clip right after the absurd claim in your edit, then follow it with a bruh sound button for the letdown, or lead in with an oh my god meme sound button when the setup needs a bigger gasp first.
حول هذا الصوت
A very short spoken clip of a voice asking 'Tá me tirando?' in Portuguese, the incredulous phrase for are you kidding me. It lasts just over a second and lands as a blunt, disbelieving comeback. The feeling is funny and mildly confrontational, like calling out nonsense the moment it is said without needing a longer explanation.