I didn't see this either,
I'm glad they are being thorough, & hopefully if they see him during a flare, they'll be able to pin point for sure this time as to whether or not its Chrohns & treat accordingly....DDs Gastro said they can't unless during a flare, hence why she has a "probable" IBS Diagnosis, due to A&E diagnosing collitis when they saw her during a flare up
I was originally DX with Chrohns myself, but mix up at the hospital Due to Gastro retiring, meant lost results, & re testing which came back clear so labelled it as IBS instead
The GF diet didn't help me, but like my own DD I do know cutting out wheat & Diary if having symptoms helps due to them being hard to digest foods.
Dietitian & Gastro we saw both agreed that the Rice, a little fish & tumeric diet I put DD on for a few days was the best thing to do to stop the diareah, as white Rice is the best none irritant bulking food, Tumeric is used in Asia as a stomach medicine, & is in curries to protect the gut against the bugs that form more easily in such hot countries
So I would highly recommend feeding him that for a few days, along with electrolyte powders such as Diarylite if he'll take them,,,if not Coke & Crisps contain the sodium, pottassium & Glucose etc that are in the Salts....... dehydration due to lost tissue salts & therefore electolyte imbalance actually cause Diareah .....hence why "travellers Diareah" can often be down to dehydration.
We also swear by VIRIDIAN Gut Flora Powders,
& if he's big enough I can personally recommend a herbal supplement "Cats Claw" it helps heal a "leaky Gut" imflamation etc etc, brilliant stuff, sorted my problems out completely, but sadly not suitable for Kids, though at 14 he may well be big enough??
Also Spirulina as mentioned with a link on the Raynauds thread, it also contains natural enzymes, which aid digestion etc, along with more digestible iron than liver etc etc
Also, has he been checked for Pernicious Aneamia???.B12 deficiency....that might be another avenue to look down, as it involved the gut, various forms of it though, some where the gut doesn't produce the need intrinsic factor to digest the B12, & it is notoriously hard to diagnose in some people...lot of it in mine & DHs families, so I've still not ruled this one out for us as my side have the Hereditary form. Spirulina can help with this too, my SIL swears by it for her PA
I hope you get to the bottom of it & get him some proper help real soon, I know too well from my own DD how distressing it is to watch them go through it & feel so powerless to help :( so I really do feel for you