Your ds is very lucky that you have questioned those you work w/ & did not follow their advice. I imagine others haven't been so lucky.
You said you are a nurse. There is a group of nurses called "Nurses for the Rights of the Child." You may want to look them up for support as a nurse w/ an intact child & to possibly educate those you work with.
There is also the group, Doctors Opposing Circumcision, that have a number of educational materials.
Unfortunately, those you work w/ are completely wrong. The foreskin in an immature penis is fused to the glans (much like our fingernails are fused to our fingers), which is part of what makes circumcision so bad - the foreskin is forcibly separated from the glans before amputation. This is also part of what makes circumcision after sexual maturity less traumatic because the foreskin will most likely be separated already (not all males end up retracting, but most do by sexual maturity - even those who don't can go on to have normal lives, so it is not worrisome). It is my theory (don't knwo that it's ever been studied) that the reason why you hear so many stories of "he just had to be circumcised at x age," is because of forcible retraction & the problems it causes. It may not *look* like it causes problems in the beginning, but since the foreskin is supposed to be fused to the glans, it causes problems down the road. It is also related to the incorrect assumption that a boy should retract by x age. It's also my theory that the studies claiming a reduction in UTIs in circ'd babies is because the intact babies are forceably retracted & this makes infection, bacteria introduction, etc. likely.
The penis owner is the one who is in charge of retracting, no one else. As he gets older, he'll likely begin to play w/ it which will aid in the separation process. Past puberty, if he isn't retractable, a hormone cream (can't remember what it's called) can be used to see if that will help. Using this prior to puberty though will likely result in him returning to non-retractable once the cream is stopped.
Again, I think your son is very lucky that you did not follow their advice w/o question. I think you are in a unique position to educate those you work with & possibly prevent other boys from being harmed. Much like we don't clean the insides of baby girls (just what is seen), there is no cleaning required of what is not seen in boys.
I hope you will stick around. And, feel free to ask more questions. You've got one lucky boy there!