I think "fit" is referring to ability to get along with the rest of the team, regardless of ability to do the job. They aren't quite opposites, but they are mostly unrelated.
It can mean that too, yes, but if the recruiter word-by-word says 2. then it could also mean 3. But then the rest the rest of the argument quite some weight since 3. is not rare anymore, as it's included in 2., too.
