Sorry for the really delayed comments! Hope this isn't too late to be helpful.
Rachel, this looks like an interesting project. I like how you are planning to capture the data in multiple ways, from survey, to more individualized questionnaire, to the focus groups. I would recommend though keeping the questionnaire short, as it might seem a little overwhelming to students (like myself) to have to give so much feedback. I do think having both is important as I do think there is some pressure to conform with group opinion, especially among medical students about such an important topic, and you may loose diversity of opinions if you limit feedback to just a focus group.
Are you thinking about making 2 publications from this data? One about the focus groups with the families and the residents and medical students about perceptions about empathy on the wards (the focus groups that are informing your videos) and another about the medical student reaction to the videos? It sounds like you are going to put a lot of effort in so it might be worth it to divide it into 2 publications.