DSP + IBS 2

I made a post recently with some very helpful information and knowledge from some wonderful people here. I had expressed my discomfort with what I’ve been told is IBS but at this point I’m not even sure anymore if it is IBS! Thank god for my next drs appointment that’s coming up, as there is many things that I need clarification on and most likely more test!! Clearly there’s some underlying problem/s I have that need to be resolved. The discomfort in my stomach, the fatigue, Brain fog, the constant use of the bathroom, sometimes even barely making it, having to cut out all processed foods, I only eat things that doesn’t include gluten, I stay away from anything that has fibre in it also.. many also suggested the fodmap, to which hasn’t helped me at all sadly. I’m wondering if it’s more than IBS myself.. (This Was more so a recap of my post so people can understand) ..

regarding my last post about If people were successful or not regarding the approval of DSP with IBS.. Now my question is, what paperwork did you have to provide, what test did you have to do to prove you do have IBS-C/D or more!?

Assuming I’ll have to see a dietician, what other specialist should I be seeing or trying to look at. I already have Endoscopy & Colonoscopy reports as well as Allergy blood test alongside, Celiac test. What more do I need to provide?