I found some pictures of Neofinetia falcata 'Kouhou' 黄鳳 and its flowers visa search. It has a very nice yellow color, even after color correcting the photos using a white object in the photo as a reference. on the ones I found is quite pretty. One of the things I like about Orchids Limited is that they are very honest about describing the plants.
Here's a link. You are right about the rambling roots. I suspect that they are too inflexible to train without breaking.
Your Kouhou sounds like a great plant.
I believe most experienced Neofinetia collectors know that all but the lightest colored Neofinetia flowers come from hybrids. There are true yellow Neos, but the ones I know of bloom white then yellow slightly over a few days. I don't think it is in any way dishonest. It is common for the Japanese to described Neofinetia leaves as blue.