When I went carnivore everything was great except for bowel movements, I mean they were better than on plant-based, but dairy slowed things down significantly. Sparkling water helped for motility. If you HCI or bile is not working properly, then meat and fat only won´t work, unless you eat rendered fat such as lard, since its super soft. There is an adaption period, surely, but if after some time you still have issues with digestion, then other solutions might need to be looked out for, such as adding veggies. So now with almost every meat meal I eat tomatoes, onion, squashes, bell peppers, aubergine, pumpkin, olives, capers, avocado and so forth. Then some specific berries and nuts such as cranberry, black currant, walnut, hazelnut, brazil nut and sometimes pumpkin seeds, allthough i find the oil is better. I read that if you have digestive issues selenium can be beneficial. Lately I do crave sardines and brazil nuts, both high in selenium. I also try and focus on mag and copper, so pumpkin, hazelnut, walnut would be a good non animal option. for copper liver would be best, but i have issues digesting it. 100 percent chocolate with zero additives or sugar is great as well for minerals such as mag, but finding a dark chocolate that has zero additives and tastes good is hard. Only issue is that its a high ox food, but if you just eat a bit, the benefits, at least so far, outshines the neg for me. Motility improved.
So I focus on foods that are low carb, do not have too much vitamin A (to avoid V A toxicity) and have low oxalate amount. Everything soft makes digestion easy, hard things make it worse, because of low stomach acid. If you were to eat potatoes at least eat red skin potatoes, they are lower in carbs, medium oxalate and have a lower GI, among other things. Forget white or purple potatoes. Same as with all color varieties of sweet potatoes, all of them have high ox. Too much carrots I would be carful with, since they are way too high in A and hybrid.