Hello BV_92
You don’t have a Mobilis pass, because Geneva is not in the canton of Vaud. I suppose the destination « Bougy-Villars » is mentioned, and you have also a via “Bus PAG - Rolle”.
You should ask the SBB if it were possible to include “Mont-sur-Rolle, La Ferme” as via. The system generates this via: “Bougy-Villars - Bus PAG - Rolle - Bus PAG - Mont-sur-Rolle Ferme - Bus PAG - Rolle - Genève”. But the price were higher, I don’t know if it were better as to buy tickets.
Kind Regards
Danhiel