It is totally dependent on your state EMS rules.
As an EMT, you can't be a "nurse" because that is a protected professional title, and you don't hold the license.
For example, in NC, an EMT couldn't do this unless the medical director in that county had approved him, and authorized protocols for him to work under. If you administer meds that you're not trained on, you will likely be in violation of your state's scope of practice rules. You could use your license, AND if something were to go wrong, you would be at great risk for claims of negligence and gross negligence.
You and the camp operator really need to work together to make sure that you are on firm footing before you begin!