I too have right diaphragm paralysis. Happened a week after thyroid surgery. I was on O2 24/7 but have gradually been able to give it up. I get a little SOB with activity sometimes but if I sit & slow down I am better. I think my body has adapted to the situation as my diaphragm is still paralyzed according to X-rays.Good luck & feel better!

I will definitely have them do a SNIFF test.

https://pubmed.ncbi.nlm.nih.gov/29243467/
High-resolution CT of the lungs: Indications and diagnosis