Welcome to the boards Slippy,
Sounds like you may have got some poor info from the get go. I'm sure by now you know to get rid of the red night light and that the temps overall are too hot.
The bulb you are using for UvB, is it a PowerSun 100 watt?
The bulb is usable but not really the best for your needs. I started out with one for my first veiled. Although I had not issues and all turned out fine, there are several better and safer ways to provide proper UvB and heat.
Problems arise when using the PowerSun 100 watt for chameleons, in many forms.
The bulb needs to be close enough to the animal to deliver off the propper amount of UvB, yet also provide the proper temperature range. That is very dificult to achieve with chameleons, and especially young chameleons. Chameleons don't require that much heat. If the basking area gets to hot you have to create a greater distance between the basking area and the bulb, and while this lowers the temps it also lowers the amount of UvB available for the chameleon to absorb.(looses its intensity with distance)
An easy fix is to get 2 seperate bulbs/fixtures, to work together to get the proper amount of UvB and heat.
Ideal set-up would be:
ZooMed ReptiSun Linear 5.0 tube 18-24" with the proper fixture
Incadescant Household bulb (25-75 watts, depending on the ambient room/temps)
The ReptiSun for UvB and the house bulb for UvA and heat.
For a Veiled of that age you should be at 82-85 degrees in the basking area and not hotter. You may need to try different wattage bulbs to achieve this. I keep my youngsters basking spots right around 83 degrees.
You also need to create a temperature gradiant to allow the chameleon to excape the heat to ensure they don't become overheated. ie:83 degrees in the hot spot, 78 at mid cage and say 74 at the bottom. That way if they get to hot that can choose to cool off as needed.
The use of proper lighting and live plants will achieve the best results. It will create humidity and cover for the chameleons. Humidity isn't as big of a concern for Veileds as some of the other species, yet does aid in hydration and help during times where the chameleon is shedding thier skin. So I would advise the use of live plants over artificial any day.
I would discontinue the use of the Powersun all togeather and replace it with a regular house bulb that can provide the proper 82-85 range in the basking area. Your chameleons will survive a day or two without UvB. Go out and get the proper lighting I recommended above.
Your chameleons will be ready if not already for seperate housing very soon, you might want to get an extra cage and lighting set-up while your out. Once they pass 3-4 months keeping them together will eventually cause death for one of them, through stress and or physical injury. They are solitary animals, and are very teritorial.
Sang posted the raisingkitty weblink above, it is a much needed read and will explain how to properly raise veiled chameleons.
We want nothing more on this forum then to see chameleons thrive in captivity, and we will help as much as we can. You as the owner need to put the advise into action to ensure the chameleons live a happy healty life.
-Jay