This is a spotted-tailed quoll.
This is not a quoll. It is a sooty owl, described as the Jack Russell of Tyto owls because it’s both small and shirty.
This is not a quoll. It is a quokka, so at least its name does start with the same first three letters as quoll, and it is a marsupial. Quendas are another such animal.
This is not a quoll. It’s a rather large brush-tailed possum.
This is not only not a quoll, its kind is partly responsible for the localised extinction of quolls in Central Australia. Also it smells horrible.