Viable Chameleon Eggs?

[TribalGecko]

Hi, just a question about chameleon eggs. I find myself with a rather large reptile collection left here by my INsignificant other. While I am great at cage cleaning and feeding, I do not know enough about the different reptiles AND I have a incubator full of veiled chameleon eggs. I have been doing some reading about them and feel horrible now because they are being house in two tanks, two females and one male in each and now they are adults and probably hating it everyday. The goof has up and left them and I have to figure out with to do with them because I can't stand to see an animal uncomfortable. I kept telling him I didn't think they should be housed together like that! Anyway, to my question, how can you tell if the eggs are fertile or not? I hate to keep the incubator running if they are not. The first clutch was laid in July and they LOOK great on the outside but when one was candled recently there was no developement seen, just a small red ring. I don't even know if you CAN or are supposed to candle these type of eggs. The thermometer in the incubator reads about 85 degrees which I think might be too high from what I read but I don't know how to adjust it. Ugh!