I am so glad for him that is is opting to flush rather than do surgery. He should be able to flush a stone out without problems. Just make sure he uses a flush with Epsom Salts . They will dilate the ducts and allow painless passage of even very large stones. (I passed some from my liver the size of a small walnut------I had my gb out last year. The surgeon lied to me when he told me my symptoms would go away with the surgery. I was still miserable with pain, nausea, diarrhea and all of that).
Try the Hulda Clark flush. It is easy for beginners and make sure you follow it to the letter. You don't have to do all of the cleanses that she specifies, but once you see how well you fell after a couple of flushes, look at the other things you can do for improved health.
Use a good psyllium based product to get your bowels moving and toxins out of your system.
Good luck on your first flush.