I cannot answer your question. I'm so sorrry about your daughter's problem. However, I want to tell you what my mother did years ago for my sister that I truly believe saved her life.
My sister has a problem like your daughter's. It is so bad that she was in the hospital for it several times, once so bad that they thought the blockage would necessitate colon surgery. My mom is a really practical minded woman. She had no guidance from the doctors, but tried this on her own and it worked.
No processed foods. Very little meat. Lots of vegetables and fruits, beans and other protein substitutes. No refined sugar. No white bread products. Prunes every morning.
If my sister strays from this diet, she becomes constipated. Constipation for her will end up in a hospital visit. There is too much at stake for her to stray from this diet.
I urge you to consider doing this. I know it's more expensive to eat this way. You actually have to figure out, kind of like vegetarians, how to get a balanced diet without much meat. You have to be more creative in the kitchen too. But I promise you that if this works (and I truly believe that it will), that your daughter will feel SO much better that she will want to work with you to eat like this. Please try it.