It's not a given that they'll beat Bayer at home. They might beat BATE, but wouldn't shock me if they fucked that game up too. This is Roma we are talking about.
A draw away to Leverkusen is not that bad considering the group. barca will win all their matches and the three teams left will fight for one spot. Basically Roma and Bayer fighting for that spot and Roma getting a point from Germany is a huge advantage for them,.
Roma is a joke. IF they manage to sneak out of this group, they'll get crushed by whoever they come up against in Rof16. Worst defensive line in CL. Florenzi-Manolas-Rudiger-Digne is absolute trash defensively.