Earth,
I am a special education teacher and have had students with autism in my class. I don't know the adults at the camp, but the fact that there is a 1:2 ratio tells me they are responsible and I imagine that they would be knowledgable about autism.

I'm sure that knowing that doesn't ease your anxiety, though. I have had parents who feel this way when their kids are in my class (usually at the beginning of the year) and I try to reassure them that they are in an environment that is not only positive but accepting. It is good that your son is around other children. It is my opinion, through observing students with autism, that they can be aware of their environment even if it appears that they aren't. An example of this includes a student that was in my class for three months. I didn't notice his underlying emotions in the three months, but when he had to go to another class (a specific class for autism), he cried and wanted me to give him a hug. I was really taken aback by this and it has really increased my awareness. I haven't had enough experience to say this is true across the board or even guess if it is true for others. I just thought I would share my experience to let you know that I do understand.

I know, because I frequently deal with anxiety, that there is nothing I can do to ease your stress. I hope that knowing that I understand helps. Take care and let me know how it goes