If you have stomach/digestive issues, most forms of soy are probably not a very good idea, as these are quite hard to digest fully and completely, even for people with healthier digestion.
Fermented or cultured organic soy, is much better. Things like organic forms of Soy yogurt, Miso, Natto, and even Tempeh (unless you have mold issues) are some forms. Actually, Tempeh has a lot of fat in it, so might cause issues for you.
I'm guessing dried, non sulphured fruit, certain grains, low fat dried goat milk (not sure they make this though) might be some foods to try.
Btw, not all fats are created equal. Some are much harder to break down and digest than others. Coconut oil for example, is one of the easiest to digest fats, and the body breaks it down almost as efficiently as a carb. Granted, with your issues you don't want to eat any amounts of same, but maybe try a very little at a time and see if you get the same reactions. If not, adding a little is a good way to boost calories.
If you don't like the taste of turkey jerky, what about good smoked salmon (like the Costco Wild Alaskan stuff)? Wouldn't be good for any longer periods of time, but a couple of days should last well enough.