I've been going all over Southern Elsweyer to runestone node locations to interact with a psijic portals to get Dov-rha Sabaton Toe Cap. But after 6 hours of gameplay there was not a single portal.
Are you harvesting the runestone nodes? Psijic nodes can appear only if the runestone has been harvested.
When I went for this lead, I just ran a route harvesting runestones and psijic nodes over and over. Took quite some time, about 4 hours for 3 evenings, so about 12 hours. Doing it off hours made it less likely somebody else harvested the psijic node before I got back to it.
Maybe instead of going "all over", try doing a smaller route, such that you come back to the first one as it's respawning. The more times you can harvest the runestone, the more opportunity for a psijic node to spawn. Six hours with zero psijic nodes makes me think somebody may be harvesting them before you get back to them; that would be some extreme bad rng otherwise.