I think the Passion flower has everything to do with love. The love Christ had for the Father in complete abandonment to His will. The love Christ has for us in being offered up as the only pleasing sacrifice for the sins of the world.
Emmanuel de Villegas was not an Augustan friar, but an Augustinian friar (just a little misspelling.)
I enjoyed your article and have loved this special flower since I was a child growing up in New Orleans. JCM