Hi again! I found more stuff. I was looking for a peaceful outcome with Garth and Galliano. And I found the option where we hid Garth on that comet, on Bradley's ship. As a result, after choosing between "New Life" and "Biotechnic", we still have the "Battle of Power" quest. And Garth now has this interaction after his last line after I destroyed "New Life": "He returned back to his hideout in the subway" (or whatever that line was)