I know this post is a bit old now but, did you take any medical examination for stool, urine, and blood?
Bowel incontinence is a severe form of constipation and there are many causes. I`m saying this because I had to deal with incontinence and I was usually constipated. Also, I took stool examination and it turned out that I had 2 viruses in my intestines: Helico pylori and Giardia. These two combined, cause incontinence, slow intestinal motility and sometimes pain.
I think sometimes you need to have some examinations just to make sure these viruses / bacteria / infections are not there.