L.C.
Hi J.,
In my mind, hitting is hitting and if the camp personnel can't protect ALL the campers, it is time to demand money back and find other childcare arrangements. Most concerning is not the hitting but how it wasn't handled. If the special needs kid or any other is hitting and that hard, then the child needs arm's reach constant supervision. The camp could even require that the family provide or pay for someone to one-on-one supervise their child to ensure the safety of all the campers.
I'm pretty protective of my kids and that is my opinion.
Good luck with your camp situation.
L. C.