Can't 'Split' versions of movie if the movie title is one word

[hornakapopolis]

The ones that show the split options and the ones that don't are all named following the same format.

.../Movies/Alien (1979)/Alien (1979) [Director's Cut].mkv
.../Movies/Alien (1979)/Alien (1979) [Theatrical].mkv
.../Movies/Alien Resurrection (1997)/Alien Resurrection (1997) [Special Edition].mkv
.../Movies/Alien Resurrection (1997)/Alien Resurrection (1997) [Theatrical].mkv