When I researched pandurata it said for bloom you need to keep the division to at least five pbulbs. I purchased mine a couple of years ago from Petite Plaisance with five pbulbs. It grew one pbulb last year but no bloom and this year, two pbulbs and each one gave me a spike.
If this were my plant, I would repot it into the correct size pot. You can probably reuse the same pot it was shipped in by sliding the plant to the other side. This species grows basically in a straight line and is not one that climbs on itself. When it blooms, the spike comes from the middle of a new pbulb and is pendant. The pbulbs also get very heavy as they get to be blooming size.
Mine is growing in a 14" basket, lined with the coir fabric mat and the media is CHC mix. They like moisture retention but good drainage. For me, the rhizome between pbulbs is quite short instead of the long rhizome your plant is exhibiting between the old and new pbulb. When I repotted this spring, I just lifted it from one basket to the bigger basket and filled in with more media so had very little root disturbance. If you are comfortable with the bark mix in your area, I wouldn't change the media as long as you understand it.
Here are some pics so you can see the growth habit of the plant.
And now the beautiful blooms - they have a light citrus fragrance mid-day.
Good luck - Brooke