Cutting open your dead chameleons is an excellent way to learn about them and their health. I open up almost everything including my pet chickens that have died or been culled (there are only so many roosters you can keep!). You will learn a lot.
The pictures that most caught my attention were the ones showing the pale cream/tan colored mass in the chest. Do you know what that was? It looks hard (because there were straight lines and angles rather than a soft oval shape). Was it hard? Did you cut that open? I think it is too high in the chest to be the stomach but I could be wrong. You can see a tiny bit of what I think was the stomach (cream colored) nestled behind the black (normal) intestines in the last picture.
If it is not too late, try to identify what that structure is. In the chest, there is a tiny heart, lungs, liver and esophagus. The stomach is a little hard to tell from the esophagus. That's pretty much the main organs you can easily find. I wonder if there was a blockage in the esophagus or maybe the stomach. Lungs are hard to find. Lungs go the whole length of the body. The digestive tract is easy to separate--just start at one end or the other. I've seen a couple of tumors/lesions that looked very similar to that attached to the livers.
You did a great job on that dissection, by the way. It isn't easy to do.
@Mawtyplant @reallyfunguy