I see you're still struggling. I'm sorry that you have to go through this, but it's for a good cause. Once the healing is complete you'll be free of reflux. I agree with the GI who suspects swelling is the issue. Keep in mind that it takes 6 months for the majority of the healing to occur, and a full year for the rest. You're still at the infancy of your recovery. It just takes time.
If your wrap is still swollen, and presumably is also fairly tight, what's happening is that you're still getting some residual food sitting at the wrap site. That food ferments and causes pain and something akin to reflux.
Unfortunately it's just something you'll have to deal with. Presumably your reflux was pretty bad or you wouldn't have had the surgery, so in the end you'll be glad you had the surgery. It just takes time. Patience.
It will get better!