You'll get used to the listening in time. So, what happened? First of all being "penalised" is not the issue. You were told that you misunderstood something which means you have something to learn. Are you more interested in the "points" or the learning? If I sound harsh I don't mean to just realistic. In the beginning, I hated the listening but now I can write something correctly even though I may not know what it means. :-)
"Are they not..." is normal question word order: auxiliary verb (are, is, do etc, etc) then subject (they, he, Jane...) then the rest.
When you have : "Aren't" the "not" is stuck to the "are" so the "they" doesn't fit in there. So, you just dump it at the end. Yes, I too like the "jammed together" instead of ol'borin' "contraction". Keep smiling.
When the sentence is spoken the voice says "American
e" so it's the only answer.
When it's written English it doesn't define the sex of those Americans so it can be both "American
i" or "American
e", both will be correct. But since in Italian you only use the feminine when you are sure that all participants are females Duolingo proposes the masculine as the 'default' answer. But both are correct translations.