If you think you need the surgery you must make up your mind that you need the testing too. It's not fun, but if it shows that surgery is not the answer you save yourself a lot of pain and recovery and money. If you do need the surgery it can show the doctors what type would be best for you.
I was about
the worst patient to ever have these tests. My gag reflex is horrible! But the results proved that I have a weak swallow and my valve was wide
open. So I needed a Nissen type surgery, but only would tolerate a partial wrap. The doc got it right and I can swallow without things getting stuck. Also I have no reflux into my esophagus anymore.
You probably won't have nearly the trouble with the test as I did. I'm old and had polio as a child. So get it done and stop worrying. The only alternative is to not have the surgery at all and not get better.