How can I help my 11-year old brother-in-law to stop pooping his pants?

My husband and I have been taking care of his two younger since October of 2024 because their mom had her stomach cancer come back. Their dad is incompetent and can't take care of himself let alone his children. I've previously lived with my husband and his family a year and half before we got married and moved out, I was their Nanny so I have been with them and know their situation very well at this point.

The 11 year old boy has very high-functioning autism and ADHD and also struggles with encapresis, meaning he poops in his pants instead of using the toilet. He will use the toilet when he decides to but 9 times out of 10 he will just use his pants. He gets bullied at school and is very insecure but refuses to try and help himself and fix his own problems. He will not clean himself unless you make him. He lies every time you ask if he's had an accident and now we have to always check him, he'll sit in it all day at school. I've tried to do everything the Internet tells me. And yes, we know we need a therapist but right now the therapist will not accept our power of attorney papers and we have to wait till their mom comes back from another state after she gets done with her extended cancer treatments. She's gone for months and she has not been helping us with getting the proper documentation for her kids to go to the doctors. We have been living by the grace of their doctors, they let us in when the boys really need it. So in the mean time, as we are fighting through that process, I'm just asking for any advice. I am a Christian so I am open to religious advice too.

Anyways these are the things I have already done...

1)I made him have scheduled bathroom breaks but he has a full blown meltdown every time I remind him (I even give him a 5-10 minute heads up) he just doesn't want to stop playing or doing the things he wants to do.

2) We have brought down screen time to literally only 5 hours a week for the most part. They get movie nights on Saturdays and game nights on Sundays. Every now and then we watch YouTube to do projects together.

3) I did a reward system, he got candy and video game time when he pooped in the potty I'm working on another idea where instead of him only getting to play video games if he poops in the potty, he gets 1 hour base-line every week and I'll add extra time when he does go to the bathroom (15 extra minutes every day he does it)

4) I try to have him eat healthier foods. He does not like vegetables to save his life, but will eat an apple here and there. We are going to try cutting out bread because so he doesn't struggle with constipation. But he has problems with or without the constipation.

5) he's in charge of cleaning the bathroom so he feels more comfortable in there and has more confidence in himself associated with the area.

6) I try talking him about it, asking questions he doesn't want to answer. What I know is that he doesn't use the bathroom at home because he doesn't feel like doing it (he says he doesn't want to get up off the couch or his bed), he doesn't like going at school because there is someone always in there, even in the nurses office. He does not want to use the teachers bathroom. He says he doesn't think his poop is gross and doesn't get what the big deal about it is. Even after I have conversations explaining it to him. He gets bullied for it and is very insecure about it, crying when I try discussing it.

7) We never yell at him or punish him for having accidents, we just check him and tell him to clean himself, sometimes he throws fits when we make him, saying he doesn't want to do it. The only time he'll get in trouble is when he makes a big mess in the house with his poop and doesn't clean it up and when he steals his brother's underwear instead of putting on a pull-up. He has to wear pull-ups because it became way too expensive trying to always buy new underwear.

I'm a stay-at-home mom now because him and his brother both have special needs and my husband and I had our first baby on December 10th 2024. I have the time but not the resources at the moment. I'm always having to search my house for poop because it'll fall out of his pants (he never fixes his pull-up so it falls out of it) he will scratch his butt in the middle of the night and just wipe it on his pillows and bedsheets. He won't wash his hands unless we tell him too and he'll literally try going to church with clumps of poop still in between his fingers. I'm trying to be patient and positive and gentle with him but I am firm when I need to be.

I know he struggles with depression and has always been a depressed and angry kid since Covid, I have been stressing the boys' parents to get both of them into therapy but they never ever made the effort to do it. Now they are dragging their feet with helping us get the papers we need for us to take them. But I also understand some of you might say it could be sexual abuse. To be honest, it would not surprise me if something happened to him, not accusing the parents or any family members because I have no idea who it could've been. It could've also been a teacher or another person in his trailer park. He won't talk to me or anyone about it. He was exposed to adult entertainment when he was younger and we've had to separate him from the kids who live in the trailer park because we caught him sexting to another boy who visits his grandfather there from time to time, they were doing it for 6 months and had plans to enact the stuff they were saying to each other, we found out as soon as we took the boys in. My husband had a feeling something was up and looked on the boy's computer. Again, therapy I know... It breaks my heart that I can't do it right now and at this point I'm having to press the big red button, the only problem is that we are completely broke and no one is willing to give us resources to where we can get affordable legal help or an affordable lawyer.

My husband is 21 years old and I am only 20, this situation is a lot on us and we have no one who is really helping us except for our church who's been helping us financially with making sure the boys have what they need and for holidays and birthdays. My mom had to move to Texas, we live in Pennsylvania, my dad lives in New York and my husband's family are always either busy or causing drama and making the situation worse. I love these boys dearly, they are my kids in the same way my baby girl is. The Lord called my husband and I to take these boys in after he provided us with everything necessary to do so successfully. Bedtime stories and Bible studies every night, art projects once a week, game nights and family nights weekly and my husband plays outside with them and has sword fights and gun fights. We try our best but they have a massive mom and dad size hole in their hearts, nothing can really replace them and God is the only one who can really give them peace. The 11 year old struggles with God, we pray for him and answer all his questions and encourage him to talk to us. He's been coming closer and closer to him, praying for his mom and dad to be better. Asking if maybe y'all can help him with praying for him and his parents too.