I have been keeping and breeding snakes for over 20 years now. I volunteered at several reptile exhibits and a pet store growing up. I have lots of friends in the reptile hobby and have worked with almost every reptile and amphibian available in the trade. I have had to force, assist, and tube feed snakes for many years and have had great success with all 3. At the exhibit we would start out by trying assist feeding which was the easiest on us and the snake, but if that didn't work we would go to a general force feed. Now some snakes get very stressed out and actually try to reject the force feed so if they struggle and reject the food the end result was tube feeding. Our tube feeding was different for every snake depending on species. Some got pinkies with a pinky pump, some got raw egg mixed with vitamins and some even got a mixture with chicken baby food and vitamins. When force feeding baby venomous snake we used a table and a thick sponge, some forceps, and a ballpoint probe or a restraint tube with a pinky pump or feeding tube. I will say this from my experiences with baby garters 95% of baby garters that won't take food on their own (I mean when you have tried all food sources for garters) are failure to thrive and have something going on on the inside of them and probably won't make it anyway. I never give up and assist feed any that won't eat cause it makes me feel better knowing that I tried all I could do, but in a lot of cases I will get them eating and then find them dead in a couple of weeks so we never know what's going on inside these little gems, like Steve said in this hobby unfortunately we have to understand that all babies are not meant to make it. Just remember when force feeding use caution and make it as quick and easy as possible so you don't stress the animal too much and use smaller prey items that won't be hard to take down.