Fire's the only thing that ever worked for me. I've gotten B.gigantea to
germinate this way, and also a large-seeded variant of B.liniflora from
the Darwin area. I suspect all the large-seeded Byblis might be looking for
fires.
I suggest sowing seed on the soil surface about a week before doing a burn.
Let the seeds moisten this way before the fire treatment.
There's a very well written, and scholarly account of fire-treating Byblis
seeds by some extraordinarily reliable source in CPN 22:1&2.
:)