The thread title says "second interview advice". So this is the second interview?

The second interview is ordinarily not about competence. Your resume, the first interview, and any reference checks have already established that. The second interview is about "soft skills", mainly personality and fit.

It's not about you the job candidate, but about you the person, fitting in. Work flow and work ethic may come into play, but it's mainly about do they think they can work with you? Will you be a pleasure to work with? Or a pain?

That's the only part of the hiring process I'm involved with. Competence has already been established and we're looking for someone who isn't a pain to work with all day every day. One librarian we hired floated to the top because she also does improv comedy. We saw her as someone who can not only roll with the punches, but can get to the heart of the matter quickly, and is enjoyable to work with. She's been a perfect fit.