As with many organisms two aspects of overall health have been noted: 1) food quality (Does it offer nutritional benefits that are needed?, Does it offer nutrients i.e., amnio acids, select sugars, that the ant cannot naturally produce?) and 2) gut biomes. Unless the species is a specialists, most ants encountered and kept are omnivorous. This means any given colony for a species, sourcing various foods is based on factors such as food quality, food quantity, starvation level of colony, food processing time and handling risk, just to cite a few. Most of us who keep ants may actually have a limited set of foods we offer, unlike the natural state of the ants themselves; again, unless they are a specialist. So we may want to always offer the most variation possible so if we only give our ants animal source proteins supplement with vegetable protein sources such as peanut butter. If we are offer only honey water, substitute with various naturally squeezed fruit juices, remember it is only a small quantity needed per colony not gallons! For carbohydrates, again peanut butter but also wheat based sources such as bread or crackers, or nuts and seeds, which offer fats too. The upshot is variation, variation. As for the gut biome, this is important as but biomes particularly play roles in food breakdown and nutrient absorption and possibly anti-pathogen benefits; thus, to assist in the gut biomes health food variation to the ants will assist in gut biome health.
As for Camponotus, I have been keeping them for a couple of years and to date have not had any die offs or unusual dying states, though leg twitching is pretty common as an ant is in the final moments of life. Also, some ant species just do not seem to like containerization, at least from my experience despite my attention to offering a mixed diet and relative good housing conditions. I have learned for example that Tapinoma seem to prefer and do better in containers that offer leaf litter or a similar substrate rather than a traditional formicarium set up, or that Odontomachus and all other Ponerines need a soil substrate to do well, at least from my own husbandry experiences.
Hope this bit of reflection helps.
