Complex sentence: Seeing its potential, Valentine reintroduced the demo to the band, who were uncertain on the song's sound at the time, decided to rewrite its chorus and eventually re-record it for the album.
Split into simpler sentences: Seeing its potential, Valentine reintroduced the demo to the band, who were uncertain on the song's sound at the time. The band decided to rewrite its chorus and eventually re-record it for the album.