Well, a win is a win no matter how you choose to see it, on the score board is written 3-2 in favour of Manchester United and luck too is also part of the game. Ruben Amorim is still trying to test run the best formation that will suit the kind of players he has at hand now, however if at the long run these formations doesn't work, I'm sure he will definitely dive into another one, after all he has just handled few games.
Yes, Manchester United were very lucky to be able to add 2 goals after being 2-1 behind, Rasmus Hojlund became the star of the victory by scoring two goals and giving Amorim his first victory since taking charge of MU.
This is an important win, but there are more important things that Amorim needs to fix after this game. Amorim still needs time to find the best formation, his experience at Sporting can be applied to MU because some of the players he currently has have star labels.