Place it right after the unbelievable claim in a reaction edit, then follow it with a laugh to underline the joke. If the speaker doubles down, answer with a short agreeing reaction before cutting to the next scene.
關於此聲音
This is a very short Russian voice clip saying 'Da ladno', lasting just over a second. It lands as a quick, sceptical brush-off, the kind of disbelieving 'come on' you use when a claim sounds too much to accept. The dry delivery makes the disbelief feel funnier and sharper than a longer argument would.