You HAVE to concentrate on FACT and not your own HA fiction. My son was actually born without an oesophagus so I am very clued up on oesophageal/stomach abnormalities and treatments and also on the dangers of repeated, unnecessary endoscopies. The fact is that any cancers would not be missed and the scope would not be able to pass down an obstructed gullet as you say (trying to convince yourself !!) You don't need to immerse yourself in any more medical info because you have had normal endoscopies with no remarkable findings other than pregnancy-related acid reflux which is very common and benign.
You can do this, Casey. You have to for the sake of your baby and to stop you projecting your HA onto your baby because you know it's a slippery slope.