Currently, Atlanta has secured one Champions League ticket for next season because it is in 5th place in the Serie A standings, but apart from successfully winning the European League, of course Atlanta also has the right to get an automatic ticket to the Champions League next season through the European League champion route, so that with success Atlanta winning the European League of course also provides a big advantage for Serie A which automatically now has 6 tickets to play in the Champions League next season, so I think Roma, who are currently ranked 6th, should be grateful to Atlanta because they also get the opportunity to play in the Champions League next season after Atlanta won the European League this season.
Indeed finish on 5th standings position or not Atalanta have been qualified to Champion League next season after success become the Europe League winner, advantage for Serie A competition with potential having six participants will appearance in Champion League next season if scenario of Atalanta getting loss on last two matches left and other side AS Roma must winning one match left.
I think the scenario of Serie A has six teams participants in Champion League depend on last standings finish of Atalanta, if finish at Champion League spot standings there are not space or opportunity for AS Roma but if finish on 5th standings automatically Inter, Milan, Bologna, Juventus, Roma and Atalanta will qualified to Champion League next season.
Roma need secure the 6th standings position if want get one champion league ticket for next season, if fail reach the champion league spot standings I don't think they have chance for playing in Champion League next season.