Have you tried progesterone? I find oftentimes treating the gut directly to be futile, since the problem normally stems from poor metabolism. Thyroid is at play, but finding a good product and the right dose can take many months. If you are a man, you could investigate Georgi's cortinon product, since it includes DHEA.
Also, I don't know the quality of the cascara product you are using, but the powder from lifegivingstore has been very useful for speeding up my bowels.
Lastly, white button mushrooms are much gentler than the carrot, and taste better IMO. I would try those out in some olive oil, with salt and white vinegar. They pair well with meat and eggs.