Yes, I agree and we are so happy we found this forum. I'll give Michele a little time. We both are animal lovers. I'm just a little distracted after starting new business.
Thank you all for your help.
I'm really sorry for your and your wife's loss.
Unless you had done some kind of a necropsy, there is no way of knowing why he died.
I don't agree with a lot of the posters suggesting it is because of a lack of UVB, light at night or too high temps.
Your chameleon died suddenly and rather dramatically. Something might have been going on before (as evidenced by your wife noticing he didn't drink) but maybe not.
I looked at the pictures you posted and although the pictures are not good quality, he looked a good weight and his legs looked straight. Based on those pictures he looked in pretty good condition. Except he died.
The hemipenes (those wormy things you described coming out of his vent) were probably extended because as he was dying, everything relaxes. That's not why he died.
While no UV light will cause a problem in the long term, it is possible to compensate, at least for awhile, with Vitamin D and calcium. Metabolic bone disease isn't going to kill him suddenly, either. Death from MBD is like death from osteoporosis--their bones just break and can't support the body or their is a severe calcium shortage in the blood and muscles don't work. MBD isn't sudden death either.
Incorrect lighting and temperatures (as long as the temperatures aren't so hot the animal dies of overheating directly) won't kill suddenly either. They kill by stressing the animal and the stress suppresses the immune system causing an illness that kills the animal. Again, if an animal is ill, they don't seem fine or reasonably fine and then just keel over dead.
It is possible that he had a blocked gut from the bark substrate I think you mentioned having, but again, that isn't the kind of thing where he is just going to suddenly fall over on his side and die. A blocked gut takes days and days to kill (unless there is a rupture) and there is a tremendous amount of pain.
There are so many things that could have killed your chameleon suddenly like that. A dear friend, a breeder, lost an adult suddenly from a hemorrhage in the lungs. Suddenly, out of the blue, this healthy female became critically ill and died in a few hours. He did the necropsy himself and found the lungs full of blood. Why did she bleed out in the lungs is the unanswered question, but it was not from illness (unless maybe a tumor that ruptured) and it wasn't from poor husbandry. It was sudden and he is still in shock just like you are.
Something else was going on. I think your wife should be comforted to know that she didn't kill him because of poor lighting or temperatures or other husbandry errors. Maybe he had a heart attack. Maybe he had an aneurysm. You just don't know, but I don't think it was because of poor husbandry. It sounds like some kind of a catastrophic event for your poor chameleon.
Please give your wife a hug for me. I know how really distressing to have a loved animal die so unexpectedly.