ok yea I posted the same link as your by accident. What he says is that palm fiber does not ferment, it's mainly insoluble.
I'm tying to decide whether to give this one a go, the schulze if1 and 2, or chomper.
Have you ever had success with psyllium/bentonine shakes?
I passed a lot of this stuff after changing my diet around. But it was very random, sometimes it would come out and sometimes it would be months or years before the next one.