Full reference to all audio in @Video1, the black-screen MP4: use it exactly as

Full reference to all audio in @Video1, the black-screen MP4: use it exactly as is. Lip movements are strictly synchronized with every syllable of the audio. Preserve the original voices, words, pauses, speed and timing. @Video1 supplies the complete sound mix. @Video2 is the already filmed room and children. Use its live-action appearance, mustard sofa, seated Yan, Kira's costume, warm daylig...