I have no experience of the role, but have experience of interviewing people, which I thought might help as you've not had any other responses yet?
It is important that candidates obviously understand what the role involves and what the company (in your case department?) does and can explain why they want that particular role in my particular company. I always rule out candidates that have t even attempted to understand what we do.
I would normally ask what the candidate enjoys and doesn't enjoy in their current role. I would expect that the parts the enjoy would match well with the main parts of the role they are applying for and that the parts that they don't enjoy wouldn't occur often in the role.
I always ask what the candidates long term aims are. They don't need to be exact and they don't need to involve promotions - learning around the role, rather than progressing from it would be fine. I use this to consider if we can support their aims, or if they are likely to have to leave fairly quickly to achieve their aims.
Always think about questions for the interviewer - the "standard" questions recommended by books are good to have in mind, but if you can think of more specific ones, it's better. Standard ones might be - what qualities do you consider to be important to be successful in the role? - why did the role become vacant? - what could I expect to be doing in the first six months in the role?
I hope that helps and that you get some advice that's more specific to the role