There was a person who posted a message about the large 'free floating' gallstone and I think he was trying different methods of dissolving it. It is possible that by using the various treatments that you have found that over time the stone could be reduced in size and forced out in a Liver Flush. Hulda Clark 's method using marshmallow, gravel root and hydrangia root with magnesium dissolves stones. I have read that Moritz's method uses the malic acid in apples to soften stones. I would guess that it is going to take some time for either treatment to reduce this stone. Diet is important in the formation of hard stones. A person needs to keep their body slightly alkaline rather than acid. See acid and alkaline forming foods.
I had quite a few phosphate and cholesterol 'soft' stones that were very large. They started coming out on about the 3rd Liver-Flush but tended to get stuck in the main bile duct but I was able to use massage to get them thru the tube. I could feel them pop out. Before I tried the Liver-Flush I did Clark's parasite Program, Kidney Cleanses and Detoxes for about 2 years.
From what I have read gallstone pain is usually higher in your body than what you describe. Years ago one of my first symptoms of gluten sensitivity (Celiac Disease) was pain in the lower abdomen near the right iliac crest. Celiacs and people with other intestinal problems tend to make Gallstones and have biliary congestion.