Hiya Deni! Wow, you've sure done a lot of work! :)
A colonoscopy is no help, as you can have MP in the small intestine and they don't check for that! People have passed MP immediately after a colonoscopy and a "clean bill of health" LOL!
If you are not eliminating your fiber drinks, you should stop taking them until you do. Only take a dose after eliminating a dose so you don't end up with more than 2-3 doses in your intestines at any one time.
More is NOT better when it comes to fiber shakes. Most people should only do 1 teaspoon of psyllium a day and get the rest from better fibers such as apples, flax, hot cereal, veggie juices (a little fiber always remains in the juice no matter how good your juicer is). You wouldn't try to benchpress 300 pounds would you? But that is what you are asking your colon to do and it can't. Stay within your limits. Regularity is crucial to reshaping this hollow organ. If you don't go, it piles up and creates a balloon, which then creates a stricture as the poor colno spasms to get rid of this junk, and you end up worse off than before you started cleansing!
As to whether you've gotten rid of all the MP, well, if you have an enviably flat tummy - feel your ribs, then your tummy. Is it concave, or sticking out? How's your posture? Strong and straight or stoop-shouldered? If all is good, strong, straight, flat or thinner than ribs, then you can pretty much assume you've gotten rid of it all. the trick then is to move on to liver managemnet and just keep the colon clean with one daily fiber shake and frequent enemas/colemas so your lymphatic system is then cleansed too and the liver toxins don't get reabsorbed into the bloodstream. Always have at least one elimination a day. If you don't, take steps. Don't take laxatives to have MORE than one a day.