I posted something on this last year, can't remember which forum, but you can actually force Nepenthes that are in full active growth to produce basal growth by turning the pot sideways, and elevating it above the apical growth point(s) so that the auxins do not travel downward the stem.
In about a month or two, basal growth should be visible near the base, and the longer woody stem can be removed and re potted, and re-rooted.
I found this out myself years ago when I had a large
N. x Dyeriana that became pot bound, and top heavy with large massive pitchers, filling up with water from my automatic misting nozzles. One morning, on my way out to work, I looked in the greenhouse and noticed that it had toppled and fallen over, right out of it's pot, with the stem nearly upside down, tangled and caught in the tubing and other plants; the rootball was up in the air, and near a misting nozzle.
I was rather busy with work at the time, even had a few out-of-town assignments and didn't get to my greenhouse for over 2 weeks. When I finally had the time to repot it, I noticed several large spikes coming from the base like asparagus shoots, even healtier than the long, thin and spindley woody main stem. I removed that woody stem, allowing the new basals to become the main growth points, and got the best plants with the best pitchers that year than I've even seen before.
These days, I often lift up pots, and turn them sideways, and lay the long main stem down below the root ball, and within 2 months, I have a new basal, or two.

- Rich