The example was meant as an example of a conversation. "Non lavorerò." "Forse NOI lavoreremo." The addition of the noi is emphasis. Or again, take two groups talking to each other: "Non lavoreremo." "Forse noi lavoreremo." (We won't work." "Maybe WE will (work).") I'm not sure how else to explain it.
I'm bilingual (English and Italian) and the answer "we might work" is much more natural than the proposed answer and should be accepted but it wasn't. Thoughts?
More info: Google gives me the same translation that DuoLingo uses but I'd like to point out that when I translate "we might work" to Italian it spits out "potremmo lavorare" which is actually "we could work" if translated correctly. Reverse the translation google says "potremmo lavorare" is in fact "we could work".