That would deff be neat to feed to the cham. I live in Indiana, which is close enough to Ohio... so that means I should be (hopefully) seeing some of the insect galore that is about to happen, as the article mentions that "The ones emerging in May are Brood V, which includes Magicicada septendecim, Magicicada cassini and Magicicada septendecula. ........... According to the USDA, Brood V comprises the largest swarms that are seen in either Ohio or West Virginia"
Never heard of anyone feeding em to a chameleon though......
http://news.nationalgeographic.com/news/2004/05/0503_040503_cicadafeast.html
According to National Geographic, cicadas are "high in protein, low in fat, no carbs. Cicadas spend most of their lives underground sucking sap from tree roots. The plant-based diet gives them a green, asparagus-like flavor, especially when eaten raw or boiled."
So high in protein and low fat is good. No carbs is great too..... That being said, lets jump back to the article you shared from the Washington Post....
"Fortunately, cicadas can’t chew so they don’t devour our plants and trees. If they manage to avoid predators long enough they suck up plant sap but not enough to any real damage."
So since they don't devour plants as an adult cicada, there is no worry of them having poisonous plant matter gutloaded in their stomachs.... the concern would be about what kind of plant sap they are possibly eating and is it okay for the chameleon. Cicadas are also well known bioaccumulators of mercury, and you would be putting that mercury into the chameleon.
The other concern would be, all the juices from the roots that the nymphs are feeding on for over a decade - and how that affects the overall toxic values of the cicada itself. Keep in mind that the nymphs also live in the ground for 13-17 years, depending on the species of cicada (the ones emerging this year are Brood V which run on a 17 year cycle). I'm not sure how safe it would be to eat something that’s been marinating in lawn fertilizers, pesticides and other chemicals for the past 17 years..... Cicadas that emerge in areas heavily treated with pesticides and herbicides every year could be very dangerous, as the nymphs could have absorbed the chemicals into their bodies over the course of many years.
It's a tough call on that one. I'm sorry I can't be of more help. Personally, since they live in the ground for so long and could absorb bad stuff, I'd advise against it unless you could somehow make absolutely sure that it came from an area that is pesticide-free. If you did feed some, I'd definitely recommend not to feed in large quantities because of them being bioaccumulators of mercury. I mean, very minute traces of mercury can be found in a lot of things, but in large amounts it could be very bad. In that case, use at your own discretion.
). She wouldn't tell us what kind of chocolates they were, and only said that she would tell us after we ate one and that they were yummy and "special chocolates". Needless to say, all but a few of us tried one. Tasted okay; definitely wasn't your typical piece of chocolate, but it wasn't bad either... very crunchy though as you would imagine it would be. Like a CRUNCH bar. 
You sure wasn't going to find the brand name Nestlé on these though... Honestly, it tasted worse in my mouth AFTER the fact that we found out it was a grasshopper. The thought of it was a total mind trick on your taste buds. Teacher sure got a kick out of the petrified look on lots of their faces though. Some of the students were almost gagging. Lol. Although it wasn't horrible, I've never once looked at my insect bins and thought "boy I'd like to try that again" 
