Some species in the Cattleya alliance, like Brassavola acaulis have flowers stalks that emerge from the rhizome. So maybe there are Epi. species that do this. And if this is a hybrid, it may have inherited this trait from any parents that do this. I have heard stories if people 'chids randomly throwing out flowers from the rhizime along with the usual method that have a parent that does. Just my
Epidendrum stamfordianum and it's going to flower. Epi. stamforidanum is unusal in that it flowers from a specialized shoot. Mine is flowering to at the moment.
Here is a link for a pic of the flower and some info. IOSPE PHOTOS Do you have a picture of the whole plant, or any close ups of where the inflorescence emerges. I definately find this interesting and I hope you frequently update us all!