I too am very sorry that you're at a standstill for treatment. It makes it so tough to deal with this disease, when you're looking for answers, and feel somewhat hopeless.
I've definitely been there, and when it's your child, it's even tougher. The good news is, that there has got to be a treatment plan that will work to control your sons Crohn's. It's a matter of finding out exactly what will work for him.
I'm guessing that you've been through Remicade and Humira by now. If so, then you might want to consider other anti-TNF's at this point. There are several others out there, and a few new ones that are almost to market. The most promising looking one is Vedolizumaub. You might ask you GI about this.
I really hope that thing turn around soon. Prayers coming your way.