Before I found Primal Blueprint and Mark's Daily Apple I was working on irritable bowels, leaky gut, and hay fever. They have a lot in common with Crohn's, just not nearly as severe. I found a very good book by Elaine Gottschall, called "Breaking the Vicious Cycle." Perhaps you have come across this book?
I did what she said -- it had something in common with paleo diets, and the Primal diet, except that she allows simple sugars such as fruit and honey. I got going on the honey (and peanut butter), so I didn't lose an ounce, but it was a miracle cure for the hay fever, which I had fought for fifty years (and lost the fight each year.) So obviously following her advice fixed my leaky gut.
If you go to Amazon.com, and find the book, try reading the reader reviews. There are over 200, many of whom had severe Crohn's Disease or ulcerative colitis. Many said she saved their lives. There are also websites where people with Crohn's and other similar diseases help each other get going with the SCD (which is what her system is called.) Lots of moral and practical support for people just starting it, who are seriously ill. It's extremely frightening to be that sick, of course, and that's when people who used to be that sick but later got cured can be really helpful.
That said, going Primal would probably help intestinal problems mightily all by itself.
Good luck. It's a terrible disease.