Let's look on the condition:
- the minimal number of goals they must score to get a chance to advance to the next round.
So, in test:
The Machinegunners played home game, scored 1 goals, and conceded 1 goals.
I suppose that the first part of an example answer, 1 goal, isn't correct. Cause answer 0 goals also meet the condition.
Why? Because if both teams will not score any goals, "Machines" will have have chance to advance to the next round at random.
So, authors?

btw, RUS and ENG texts are different in conditions:
RUS (strong less): максимальное количество голов, которое они могут забить, не пройдя при этом в следующий раунд.
ENG (less or equal): the maximal number of goals they may score which leaves a chance for their opponents to advance to the next round.
So?

no, because if they'll play 0-0 the number of goals scored by the second team in away match is 1, and Machines is 0, so the second team will go to the next round. It was mentioned in the task.