I personally would never feed chams crawlers or reds. They live and the ground which in itself is very unlike anything a cham would naturally eat. Worst of all is that they're prone to have parasites. I wouldn't feed them to your cham if I were you. Stick to the regular stuff crickets, dubia, butter worms, silks, and super worms. there's a bunch of others but that's what I usually use.
Hope it helps
Scott