Complex sentence: Malloy states that he was unaware of the MTV appearance until the last minute and felt that in light of this, the band were making it impossible for any singer to be popular with Van Halen fans again other than David Lee Roth.
Split into simpler sentences: Malloy states that he was unaware of the MTV appearance until the last minute. In light of this, he felt that the band was making it impossible for any singer to be popular with Van Halen fans again other than David Lee Roth.