According to Memory Alpha
, it may have been anyone.
The name of the species comes from a biography of Lt. M'Ress published by Lincoln Enterprises in 1974, which claims that the Caitians are related to the Kzinti. This is corroborated by extensive commentary by Larry Niven, author of most Known Space books, primarily found in his short story books "N-Space," "Playgrounds of the Mind" and "The Patchwork Man."
I wonder if Larry Niven had anything to do with it, or if he was just tasked with shoring up the background of her character.