@firefighter66 You are right. Every surgery has risks and has a benefit to risk ratio. Some of that is because of the skill of the surgeon, and you want a surgeon with a lot of experience in the surgery you consider. The other part of the equation is your own personal health, your age, other health conditions and if you have other risk factors. You have to ask yourself how difficult is it now to live with the disability, and how will that change as you age if there is no intervention? What else could happen in the future to make it worse if you continue to live with compromised lung function? How would your function be different if you did have a proposed surgery the good and the bad?

Since your profile says you have 18 years at the fire department, that makes me guess you may be in your forties. You should have a lot of life ahead of you. I also think that you could be at significant increased risk of lung infections because your damaged lung isn't moving properly, and it takes movement to keep clearing the phlegm out of your lungs. When that gets trapped, it can easily become an infection. Infections like pneumonia or Covid of course can be fatal, and there are also bacterial/fungal lung infections like MAC that are very hard to cure. You could experience other lung disease that takes away function and need oxygen down the road. I have a condition called thoracic outlet syndrome that makes one side of my neck and chest too tight, and I have gotten infections repeatedly because of some trapped phlegm that start on the side that doesn't move as much because of chest wall tightness. It doesn't help that I have allergies and asthma adding to the issues. Your situation has to be so much worse than my experience.

Here is some of what I found about the phrenic nerve surgery. Some of it may be hard to decipher, but you could pass it on to your doctors.
https://www.thieme-connect.com/products/ejournals/abstract/10.1055/s-0036-1588018
https://academic.oup.com/icvts/article/32/5/753/6082780?login=true
Would you consider being evaluated by a pulmonologist and neurologist? Doctors in these specialties may have a better understanding of this issue and determine how much function you have lost. You may want to make a list of your questions and keep adding to it as you think of more so you are prepared when you do see a doctor. If you do contact Dr. Kauffman, you would be asked to provide test results from these specialties. Are you a candidate? The only way to find out is to ask.