Injuries are complex and favoring one thing can cause an injury to another part. Pedro was just an example. We don't know if the original injury to Wright resulted in the additional injuries. We only know that the shoulder injury occurred at the peak of his effectiveness thanks to Farrell.
Pedro's legs went as he was compensating for his shoulder woes. All we know is that Wright had the apex of his career the night before the fateful Farrell decision. That's what we know. Draw your own conclusions.
When they were traded they were prospects who were pretty far away from the majors. Ipso facto they were nobodies when traded. You don’t become someone until you do something at the MLB level.