If you're not already doing it, you can make it a lot easier to get excess moisture out of the filling by salting the cabbage and squeezing it. I follow the method explained here and it works well.
Good call, yeah I have seen that technique before on YT. I guess stir frying in the wok gets rid of much of the moisture, although doing it in batches may add a bit of unwanted oil if you're not careful.