If its happening at your daycare... then I imagine, is it happening at home too????
What is the parents response?
Do they say anything much or are kind of reacting with perfunctory answers?
What I'm saying is... is their response to this, natural and off the cuff and real. Or does it seem, generic and un-reactionary?
Are you sure no changes has been occurring in his life or at home?
There is also something called "Encopresis" which is in involuntary leaking of poop. A medical issue.
Have the parents taken him to the Doctor?
It may be either emotion based or medical based.
Does he poop at other times of the day or only now, at nap time?
And yes, maybe he is actually asleep when he is doing this. Much like what sleep walkers do. They are not cognizant of it.
Either way, the parents should speak to the Pediatrician. To rule out medical problems.
Or hopefully, not any type of seizures or anything.
And yes, how can he do this, during nap time, and not disturb the other kids???