Can gerd lead to pain from the stomach down to the leg?

Possibly: It is theoretically possibly to have gerds cause abdominal pain referred to the leg. Very low probability of gerds causing those symptoms. Bulging, herniated, protruding, or degenerative lumbar disc more likely the culprit. I would start with a lumbar MRI scan to determine cause of the pain. Also, bowl problems, abdominal masses can also be the cause. Abdominal MRI may be more beneficial.