(((JUNERAIN)))) grrrr I'm so sorry you resigned. That pretty much ended any chance of a lawsuit== for anything.

But I can feel your anger and frustration from the way they treated you. (I'm sure the expectation of love and understanding from that type of camp added to your angst. Been there, done that.)
I also understand them needing everyone to turn in their medicines. Yes, you might have a case there against the nurse, unless their policy is not to count and manage, just to keep the medicines so children don't get into medicines except those that are their own.
I would put on my resume, if I were you, regarding the resignation that the "camp was not what they presented it as" ... if you list it at all.
This, too, shall pass. You did spend some time there and are due payment, especially when you had to have sponsors. Regarding non-profits, in many States (it might be a federal law) when monies are donated for a specific reason, that money MUST be spent on that reason only. Depends upon the contracts and donors forms' wording as to whether they can absorb your sponsor's monies.
Time to move on. Don't pursue this except for the money if the wording is good for you. If you have the list of sponsors, you might contact them and briefly explain the problem. They might be able to ask for their money back, or stop payment on checks.
And you can also write the local newspaper...
But in any of this, you need to remain calm and collected because they are going to play up your "mental illness" and "medication"...and the rest of the people will be looking for a deranged mad-woman, you know?
This is one bummer of a situation.