Place it right after the accusation appears, then follow the proof with a confused huh before a short damn to close the exchange, keeping the question as the centre of the edit.
Über diesen Sound
This is a brief spoken line, lasting just over two and a half seconds, in which a single voice asks why the listener thinks the speaker is fake, with the emphasis rising on the final word. It feels sharp and defensive, like a direct challenge thrown back at an accusation, and its abruptness makes the denial land harder than a longer reply would.