Maybe the confusion comes from grenada being a word for pomegranate? Try this link for a dictionary page explaining which are names for different passiflora - grenadilla/grenadillo.

Here is a link that might be useful: Grenadilla

Sorry I spelled that wrong - granadilla. It looks like there is no one species of passiflora granadilla, but that many different species are lumped under that name. Anybody else know?