Bio-HPF contains bismuth which is used in multi drug therapies to treat h. pylori.
Something in it must be irritating your stomach. Perhaps stimulating your digestion which is causing irritation. You said that you could not tolerate any HCl or acid so maybe the capsules are causing the release of acid. Clove can do that.
To calm your irritated stomach it might be worth getting some slippery elm powder and consuming some of that. It draws out acid from the tissues which might be soothing on your stomach.
In the short term while you have these problems it might be worth getting some amino acids from a body building supplier. Get some common essential amino acids and consume them if you can tolerate them okay. Start slow and build up. They won't need digesting and will nourish your body with the missing protein/amino acids. They are acids so only get a small amount until you know that you can tolerate them. Taking with something to coat the stomach might help such as liquorice or mastic gum.