Italy Travel with Trenitalia Pass

Hello everyone, I have a question about 3 day Italy Trenitalia Pass. I am planning to go to Bologna from Genova. As I saw tickets are not available in Lombardia region. If I buy 3 day ticket and also buy the Lombardia region extra like Tortona (or Voghera, I don’t know will they accept Voghera because it’s at the bound) to Castel S. Giovanni will that be okay? Any experiences on this? I also plan going back at the same day, for that I will buy Piacenza to Voghera (or Tortona) like the same way passing in Lombardia, will this okay? Any suggestions are okay for