I had a similar problem with my son. In kindergarten he would frequently wet himself because he is terrified of using toilets because of the noise. He didn't mind using the urinal but the teacher couldn't even seem to remember to take him to it. (it was down the hall) I live in a small town, the resources for autism up here are not satisfactory at all. I tried three schools before deciding that home school is best for now. I would like to help with some suggestions but I don't know enough about your child. Is your son scared of toilets? Does he wear diapers/pull-ups all day or does he ask for one when he needs to go? If I had more details of your situation I might be able to give you some ideas to try.My son would always ask for a pull-up when he needed to go by the time he was four. From then on he rarely had any accidents, as long as he knew I would let him have a pull-up when he needed to go. If he thought I was going to try to withhold the pull-up so he would use the potty, he would hold it in and become constipated. Basically he is scared of the toilet and refuses to use it, I have tried everything imaginable to coax him to use it.If I even tried to just have him sit on the toilet,to "practice"he would start crying, shaking, and even gagging like he was going to throw up. I knew at that point that he really was terrified, and pushing too hard was not going to get us anywhere.We tried rewards,We tried three different store bought plastic potty training toilets or whatever they are called. We tried a bucket with a plastic toilet seat on top, a camp chair with a hole in it with a bucket underneath, I tried cutting a hole in the back of his pull-up and then had him sit on a camping toilet to see if that would make him feel more at ease, that was actually the only time he successfully pooped into something other than the pull-up.This will sound insane, but we have a big back yard with privacy in some areas, so I even let him try to use his potty seat outside a couple times.I have to bathe him in a large utility sink because he is afraid to hear the plumbing while he is in the bathroom tub.I thought maybe youtube videos of other children using the toilet might help him feel like it was safe and there was nothing to fear. He ended up liking the videos, but it didn't seem to help much.He started watching youtube videos of people flushing toilets, and flushing food down toilets, and that became a fixation. One good thing that did come from that though is that he does like to flush toilets now, and will occasionally get in the bathroom tub for a bath.We actually met another autistic child that likes toilets and makes videos of different brands of toilets, the boy overcame his potty training issues finally at the age of ten or so. My son is now eight, and I feel like we have made some progress. I am hoping that any month now he might finally use a toilet. It is frustrating, and hard to explain to people who are not familiar with the autism spectrum.

He didn't understand for a while. It seems he has caught on though. He is higher functioning. He never tells anyone when he has an accident. He doesn't seem to care that he has poop in his pants. The after school care won't do anything about it typically. He is just left in his own filth. I realize they are set up for children that do not have this issue, but I don't understand how a person could allow that. I am just not sure how to get across the need to use the potty when he seems so oblivious to the normal reaction to it. Even in regular underwear.

So far my kid isn't potty trained but I don't know if she would know when kids are making fun of her. Potty training is hard but when it comes to some autistic kids it's mission impossible which really makes a parent feel like a loser. My daughter is a somewhat verbal but I can't get my daughter to just say "I pooped" so I can at least change her.

Seriously, I still think a professional potty trainer could make a lot of money if they could train autistic kids above say the age of 3. If someone could train my kid in 5 days and make it stick for a month I'd pay $1,000. You'd think you can find anything on the Internet but not this job. Heck, I'd quit my job and do myself if I had steady work and if I knew how to do it for autistic kids.

I had no idea it was so common and I feel like I can breath a little better knowing that my baby ain’t the only one 🥺🥺

Ummm... if they are letting him stay dirty there is a problem. By accepting him in the program they agreed to accommodate his needs. File a complaint. I would not stand for this type of care. It should be reported to the dept. of human services as neglect by the caregiver also. As a caregiver you are a mandatory reporter right? My advice is to report it.
As for potty issues... some people who have Autism never get fully potty trained. You can focus on it but by no means should you expect immediate results. Repeating helps... you could try a picture board showing the steps at home and request he be taken to the restroom on a timed basis when elsewhere. Say every 30 mins. Keep it as positive an experience as possible and make a huge happy spectacle when he does use the restroom. Give him a small item as a reward.