Superworms can climb screen walls and a lot of other things, just make sure when your placing it you see their little arms go through the screen and theyll attach themselves, they are near the front of their body.
I believe any feeder is capable of biting your chameleon but correct me if i'm wrong. I have never had this happen but my cousin had her veiled get a mouth infection from a mealworm bite. As long as your not feeding feeders that are ridiculously too large for the chameleon I think you'll be okay.
If your really paranoid you could cut the heads off your feeders before, but then you would have to cup feed/hand feed and if you want the cham to hunt thats not an option.
" The rule of thumb is to feed insects no wider than the width of your chameleon's head in order to prevent choking."
PS: Superworms will even attach themselves to the roof of the cage mesh and just hang there dangling their torso, my cham would love to shoot for them this way.