Complex sentence: He then asked Bobby to accompany the band to hear them play their next one-night stand, and when there, asked him to sit in with the band for several minutes during the performance, taking Tommy's chair.
Split into simpler sentences: He then asked the younger Byrne to accompany the band to hear them play their next one-night stand. While there, he asked Byrne to sit in with the band for several minutes during the performance, taking Tommy's chair.