I've played with a lot of ferns over the years and till now all of them don't realy like transplantation and dividing even less.. I guess its their slow growth habbit playing a role, that the transplant shock causes more damage and the fern dies faster than it can repair itself. Under artificial light this can even be more difficult depending on the sp.
All ferns i dug up in nature to put in my garden 80% of it died back the first year and came back the year after that. I learned only to transplant/devide ferns in the spring time this periode the rhizome has a lot of fresh young shoots and is most vital also this climate is beter for a fern, soft light and lot of moist. But this is only for ferns in the ground.
Transplanting epiphytic ferns is even more dificult, still trying to find a sp. that can take it. But till now all i ttried all died.. As if the fern has to decide on it's own where it likes it grow. A spore germinating alteady is a little rare wonder in need of special conditions, that a spore finds this in nature is somewhat a rarety, or else these would be much more ferns. So i guess if you do not transplant a fern to an absolute perfect spot (for example in a terrarium) it will not make it. For example i have a bunch growing naturaly to the damp wall at the back of my shed, i took several young plants of the wall to put them somewhere else. and i failed every single time. I have to leave them where they are..
Must say the Adiantum fragrans till now is the only fern i diveded with somewhat success. Did put a small piece epiphytic on driftwood in the damp moss above my aqaurium and it made 5 new leaves already. They are not in perfect color, but it slowly seems to addapt.. It's a first for me, all other fern species i tried failed. But it's standing under a sky light.. This picture is taking a minute ago about 8.30 AM and all artificial light is turned off.. This tank is fully naturaly lit, and pretty bright, durring the summer far over 12 hours a day..
Did the same outdoors with a Asplenium trichomanes, (Spleenwort maidenhair). Flushed all the soil from it's rhizome but this one didn't take it that well, it still is in transplant shock, definitively in trouble and loosing leaves. I'm not sure if it's going to make it. I have to spray it several times a day, so it takes up moist via it's leaves. Somehow the rhizome is refusing to make up for that, all tho it's partialy in the water. In the right hand back of the picture is the same plant i left in the pot, so i didn't transplant that one, the pots bottom is in the water. And this one doesn't have any trouble at all. And the spleenwort definitively is a fern that prefers to grow epiphytic.
Likely not at the spot i choose for it. But reportedly they also grow like this in nature at stream banks.
Anyway, transplanting ferns and give them a new substrate always is a bit of a gamble and a game of patience.