Serviio retrieves metadata for movies from themoviedb.com. When I go there and search for "I Can Dance", your cannibals are exactly what comes up. I checked IMDB to see what I could find under that title, and what comes up has this as the story line:
I Can Dance! is a feature-length story about the power of dance to transform children's lives in American public schools.
Is that the actual title you are referring to? If so, you can try adding the IMDB number (tt2407552) to your file name. However, even with the IMDB number the title has to be contained in themoviedb to appear correctly in Serviio. And I can't find it there, so the TT number might not help. It also helps to have the accurate release year in the file name ("Star Wars (1977).mkv" as an example).
I have often come across movies I've recorded from a local station, and the name they used for the movie title is different from the actual, official title. So maybe there's a different title available for your movie. The reason you are getting the cannibals is because an alternate title to that movie is "I Will Dance on Your Grave: Cannibal Hookers", and that's the best match themoviedb has.