I feel like you're getting buried in other people's threads. Please post a new thread to discuss your son's impending surgery.
Have you checked on the experience your surgeon has with the procedure?
Incisionless surgery for reflux is very new and from what I'm hearing, not as successful, but I don't know what your surgeon is saying. He may be having better luck. My GI doc wouldn't consider it because of its newness. Nissen Fundoplication remains the "gold standard" reflux surgery. Fundoplication surgery isn't any more difficult to recover from as far as eating goes, and the surgery is done laproscopically, so it's a very easy heal.
I'm not as familiar with kids getting the surgery, but I do know that so many kids get fundoplications, that it's sometimes difficult to find resources online that don't relate to kids.
Also, it's crucial to have an extremely experienced and skillful surgeon.
I also had the surgery because of asthma, so I know what you're going through.
Good luck finding answers. I hope you'll post a new thread with your issues as the topic, so others can find it and comment.
Take care and good luck!