Though it's obvious the Patch Notes confirm that Hissatsu: Yaten was misnamed:

An issue wherein the level 56 samurai ability, Hissatsu: Yaten is misnamed Hissatsu: Gyoten, which is also the name of the level 54 samurai ability. Both abilities function properly, but the only way to tell them apart is by their icon and help text.

Furthermore, using "Hissatsu: Gyoten" in a macro will properly trigger the level 54 samurai ability. However, the level 56 ability "Hissatsu: Yaten" cannot be used in a macro until this issue is resolved. We sincerely apologize for the inconvenience.