First, don't listen to people at the pet store, most of them just don't what they're talking about. The general rule about feeding is no bigger than the head/mouth. You can get some Micro Superworms if you're concerned. There's also tons of other stuff, maybe try a sampler?
http://www.lindasgonebuggie.com/page/419991568 Although, wax worms, butterworms aren't great and should be thought of as candy or a treat. Mealworms should be avoided imo. Phoenix Worms (Black Soldier fly larva) are good.
To tell if your cham is drinking look at the poop:
https://www.chameleonforums.com/threads/poop-101.120171/ They tend to drink, not all or all the time, when you're not watching.
Also, some ideas. Mine will eat just about anything so I have to be careful. She also has a thing for banana.
pieces of leafy greens
- romaine
- kale (not daily - some is great, but a lot may not be)
- collards (not daily - some is good, but a lot may not be)
- hibiscus leaves
- dandelion
- endive
- basil
- mint
- cilantro
- mustard greens
- arugula /rocket
- clover (not daily - some is good, but a lot may not be)
- endive
- sprouting alfalfa
- baby's tears (Soleirolia soleirolii)
- oregano
- spider plant (Chlorophytum comosum)
veggies - Make everything of a size that would fit in your chameleon's mouth easily
- shaved/shredded pieces of carrot
- small pieces of steamed (and cooled) squash
- small pieces of steamed (and cooled) sweet potatoes
- small pieces of steamed (and cooled) yam
- zucchini
Flowers
- pumpkin /squash flowers and leaves
- hibiscus - leaves and flowers
- nasturtium blossoms
- arugula flowers
- jasmine flower
- okra flower
- pansy flower petals and leaves
- coneflower Echinacea (not rudbeckia)
- Campanula / Rampion / Harebell / Canterbury Bells - leaves and flowers
- aster / michaelmas daisy - leaves and flowers
- Antirrhinum /snap dragon - leaves and flowers
small, occasional pieces of fruit - very small amounts
- thin slices of mango flesh
- bits of papaya
- half a seedless grape
- blueberry
- thin slice of apple
- a piece of pear small enough to fit into the mouth
- thin small pieces of organic sweet red peppers (of the non-organic foods that have pesticides on them, these are one of the worse - it goes right through the thin skin and into the flesh - so use organic)