With Pudendal Neuralgia, or any other pelvic chronic pain issue, it can be impossible to sit pain free (let alone get away without a flare up).
Of course, I'm no pro when it comes to seating, but I've learned a lot from my own experience and from listening to the 'ouch' in my pelvis. The seating I needed, was most often hand-made! (Have a look at the one my gorgeous father in law made, it's the stool with adjustable foot rest!)
Although I've worn out, thrown out, tried and tested so many more seating aids, I'm showing the ones that have lasted or worked for a while. These are the ones I often resort to.