Complex sentence: It was Mark's connections to radio personalities DJ Red Alert and DJ Chuck Chillout that initially got the crew noticed, but the original members also all had formidable rhyme skills and wrote streetwise lyrics.
Split into simpler sentences: It was Mark's connections to Radio personalities DJ Red Alert and DJ Chuck Chillout who gave the crew quick notoriety. It did not hurt that the original members all had formidable rhyme skills and wrote streetwise lyrics.