If your 8 year old son has bed wetting problems or is incontinent during the day then yes your 8 year old son should wear diapers during summer camp.
I was a summer camp worker a few years ago and we had some 8 year old boys wearing diapers and we worked with them so they would not be embarrassed and helped them get changed in a private place.
They actually changed into their own diapers but we made sure they had a private place to change into.
They would leave the diapers in a room with us and then come and get them.
Your son is not the only kid at summer camp who will likely be wearing a diaper or pull up.