Could be that they always planned to interview Brady and Moore, who can't be interviewed until next week, so this week made sense to interview Kafka and Weaver. Or they are really interested in Kafka and Weaver as serious candidates?
I think that the Saints are only interviewing people that they would hire. The first step of the hiring process is to narrow down the pool of available candidates to just the people you would actually hire. Then you start scheduling the interviews.
Even with the Rooney Rule, I don't think the Saints would fly someone in for an interview that they aren't seriously open to hiring.