At the time I took the ppi I was all over the place with visual disturbances anyway. This was about 4 years ago so I’m racking my brain to remember what. I was off work at the time and the watery vision you describe I had a lot, it was a common feature, along with general unsteadiness and wavering. I’m struggling to remember what I had before the ppi and what I had as part of the ppi side effects.
I do remember the omeprazole in particular caused me to feel particularly bad though, and I remember having a ‘white out’, which is the only way I can describe it. It was an attack of vertigo, but for a moment after I couldn’t remember where I was or anything which was different to other attacks of vertigo. All I can assume is that it was brought on by intense dizziness and visual stimuli that my brain couldn’t cope with as a result of the ppi.(?) I’ve avoided them since.
I can’t believe they haven’t tested you for h.pylori - it’s a pretty standard test really. And for gastritis to go on that long without resolving, you must be pretty uncomfortable. I did find that yoghurt caused excess acid in me - you might want to avoid it - sorry, I know that probably limits even more the things you are eating.