To clarify, the V4Lv1 device is /dev/v4lv1 or something similar, so if you can point the release vlc at that (do you have a pointer to the deb?) it should just work.

flashcamd sits there, /dev/videoX, X>0 is the push end of the pipe, /dev/v4lv1 is the pull end, and when something starts reading flashcamd opens and forwards video from /dev/video0 (a v4l2 device) through the pipe to /dev/v4lv1 automatically.