A healthy weight is usually based on the dragon's length, so do you have measurements? It's possible that your female could be underweight from being bullied by the male though. (dragons aren't very neighborly with other critters, lol :?)
And yeah! I've heard of those types of videos on YouTube but I don't have the guts to look them up, lol. Unfortunately what they usually don't tell you is what happens to the poor dragon afterwards
Plus if whatever got eaten is carrying viruses/bacteria/fungus, that could get transferred to the dragon as well.
About the babyfood- too much salt/sugars/weird chemicals isn't too great, but luckily they do sell "all-natural" babyfoods that don't have any added stuff. Try to get the Stage 1 kind (the type for the youngest baby age group); those usually don't have additives except maybe a bit of water.
The regular grocery stores near me carry Stage 1 all-natural babyfood, but if the ones near you don't have any then a health food store should definitely have some.