GERD is often caused by a hiatal hernia. If during VSG surgery a HH is discovered, most surgeons will repair. GERD is also more common among people who are overweight and can sometimes improve or completely disappear with weight loss.
I would suggest forwarding your medical records to Dr. Alvarez, specifically any pertaining to your Upper GI issues so that he can review and then tele- consult. Have you had an upper endoscopy?
I am currently at Dr. Alvarez's Endohospital (Endobariatric.com). I have met Dr. Alvarez a couple of times since arriving earlier today. He is most impressive! It is not exaggerating to say the facility is like a Luxury Resort Spa. My surgery is scheduled in the morning and after talking to several patients one & two days out of surgery, I know I have chosen the right surgeon.
I hope you can find the answers you are seeking.