I'm so sorry to hear of your sons condition. There are not many consultants who will perform surgery when there is a motility problem, however a toupet fundoplication can be considered, and the Endostim is without a doubt the best solution for those with motility problems.
Has your son been diagnosed with achalasia or poor oesophageal motility?
And did your consultant not offer some advice?
Have you tried raising the head of his bed, alkaline water, small meals etc?
I really hope that you get some help soon for him,
All the best,