I am convinced that anyone with Crohn's or any kind of gut dysbiosis has parasites of some kind(s). Nowadays it is well known how supermarket sold industrial foods, incl fresh veggies and fruits cause inflammation and immune stress as they are full of pesticides. This is unnatural and the body cannot keep up long. Therefore the outmost important first step is to switch to completely organic and then start cleansing, step by step, and working on restoring balance. It is a good thing someone has relief from pot but i doubt this would resolve the problem entirely. I hope his symptoms will not return when his immune system gets weaker. Of course everyone is his own healer and i can only give advice. I am personally not against the medicinal or recreational use of marijuana. Far better than the junk the doctors prescribe or alcohol, as a matter of fact.