Honestly, sub-q might be better but tube feeding isn't overly stressful when done right. Soaking also allows him to get rehydrated. A question though... How long have you been doing the tube feeding? The water (though I'd recommend pedialyte) isn't an issue but twice a day on the carnivore care is a bit much. I would go every 3-5 days to slowly allow his system to get going. If he hasn't eaten in a long time, it's very possible that his gut bacteria have been compromised and digesting food can be stressful on the system no matter how gentle it sounds. I would talk to your vet about adding probiotics to the tube feeding food mix. I've had to do this a few times and all you need are the human probiotic capsules. Break one into the food mixture right before feeding to help. Another thing, I wouldn't try feeding a dehydrated animal. They need to be rehydrated first before eating.