From my experience, it is up to the Director of the camp to decide who returns and who is listed "DNR". Good communication between the nurse, counselors and the director would make it clear on who is not appropriate to return.. But it is still up to the "boss". Needless to say.. they like to use their veto power. Grumble.
Just keep a list throughout the summer and discuss your issues at the end of the season with the director. Hopefully, he will take your recommendations into consideration.