I believe that Manchester United focus now is on the UEFA Europa league and on how they can be able to win it because they already know that there is no way they can be able to finish top four in the English premier league, they are still unbeaten in the UEFA Europa league competition I still believe that Manchester United eliminating Lyon is possible though it won't be an easy game but Manchester United will qualify, if they can be able to win the UEFA Europa league that will be great achievement for them as you have said because it will be like using one stone to kill two birds since winning the UEFA Europa league will qualify them to play in the UEFA Champions league next season despite not finishing in among the top 4 in the English premier league table so Manchester United winning the Europa league will a win win for them.
The focus isn't only on Europa but that's the closest they can fight now, they can't make it to the top of the table but they can manage the rest of the season and be there till the next one. Amorim will be finishing the season without any to show for his job despite bringing more staffs from his previous club to come support him but they haven't win anything, so I guess that's the reason why they are serious with the Europa league and I think it's possible.
If only the way they won their last match, they did the same thing in the Premier League, I'm not sure if there is any team that will come close to them after Liverpool but they have misuse all their opportunities in the Premier League and now, what's left for them is nothing but survival. Hopefully, they draw Nottingham Forest, I'm not sure about the winning but if things change and they win, there might be high chance of them returning top 10 else the struggle continues.