He's a good lookin boy! I agree get a lower watt basking bulb. I just use a regular household bulb. What do you use to measure your temps? You don't want him to get burned again.
All new chams should be quarantined, you never know what they've got until you get that fecal. https://www.chameleonforums.com/quarantine-those-show-animals-15636/
The vet should be able to a culture to find out exactly what type of URI he has to know the proper medication to treat with...
Some keepers do smash the heads of the superworms before feeding because they do bite and can bite your cham and I have seen pictures of where they damaged the chams eye.
Silk worms are very well supplemented theirself and do not need any additional dusting.
As for the shed it's probably ok. Veileds have some shed on them some where just about all the time. If it gets bad and stays on to long you can dip a Q-tip into very warm water and then rub the shed off...