Hi Tindo, here are a couple of good sites that explain the process. The first uses the dry pod method, which is typically considered less desireable and less reliable. The second lists seed pod gestation periods for a variety of genera.
http://www.phytosophy.org/resources/...Art001-En.html
http://www.orchidworks.com/ozone/greenpod.htm
My guess is that after all this time, the seed pod isn't viable. It doesn't look like it's nearly as swollen as it ought to be.
Julie