Crohns can be missed on blood tests. Really all autoimmune disorders can be due to the fact that some people are sero-negative. A person can have horrible RA and severe damage to their hands from it and no RA factor, which is why other tests are used to look at it from a whole.
And no, a valve is not the only treatment for that either. There's Stretta over here, though I think there's a limit as to what degree of hiatial hernia there can be before you don't qualify for it. I imagine, though, since it's newer and only recently back on the market that it might not be covered over there.

There are a couple other options, too, but you'd have to look them up as to what is offered there. Usually though, it can heal if it's not too large but one has to get their diet under control.
If he consumes any caffeine at all, even chocolate, he may have to completely give that up.

My DH has a small hiatial hernia and GERD caused by NSAIDs and caffeine (and, against my wishes, eating food he really shouldn't).
Hey, I ate white bread and didn't immediately (within that day) get sick all the time, either. Didn't tolerate whole grain very well. It's really weird as to how and when it will affect a person, some never have GI symptoms...
I'm really not that aware of food labeling in the UK. But here they supposed to list possible allergens, even if made in the same plant/ on the same lines. (some brands don't seem to comply - so I do not buy them)
This makes for the possibility of contamination from something as simple as your seasonings you use. Luckily I already mostly used a safe brand for those and didn't have to throw much away. Some "gluten free" products are cross contaminated that way with wheat flour, too.
Sometimes beef bothers me, chatting with sharky about grain fed cattle and such there may be a possible problem in that.
Since there's accumulated damage I'm mildly lactose intolerance and sometimes have problems with fructose - HFCS and even fruit can be a problem. But this is getting better. And the fructose issue isn't one anyone would suspect, though it seems common.
I mentioned candida in another thread: it's a GI yeast which does crazy things to people. IBS is one part of it. Bacterial overgrowth can look like IBS, too, and sometimes isn't looked for. These both get suggested low carb, low sugar as a diet to help with it. This is usually what people with GERD/ other GI issues are recommended, too.
Were you guys still using distilled vinegar? Anything with caramel coloring? Anything that said "food starches" or any of the other hidden ingredients?