I would arrange to have frequent, quiet meetings with the school to tell them exactly what you tell us, and to also get them to tell you what they think, based on what difficult child tells them. Let thim think you're cold and that husband doesn't spent time with his son. What they think doesn't matter, not in terms of your self-esteem. But then without getting angry with them (because you know how persuasive the kid can be) explain your side. Ask their advice. Let them know that you are aware he hates you but you're still there at the school trying to find ways to get through the barrier. let them know that husband does make efforts to spend time with him, but difficult child sabotages it. Ask their advice on how husband can get through to his son. Ask their advice on how to prevent difficult child from throwing away his clothes, his toys etc and then telling other people that someone else did it.
You know the staff aren't up to scratch at this school, but don't let thme see you feel this. By asking their advice, you're making thme feel as if you need them. You're also making them feel important, of use and listened-to. You're also making it clear that you WANT to help this kid but you feel out of your depth.
If you try to handle it any other way - such as by making it clear that you are on to this kid, you know he's trying to con everybody and you have superior knowledge - you will only make them MORE resentful, give them MORE reason to find you lacking as parents, and also give them more reason to invest in difficult child's version of events.
So go to the school, act like you're at the end of your tether, you've tried everything. Sit with the staff, all of you as a team, and brainstorm what you can do for difficult child. Even when they make idiotic suggestions nod andsmile and look like you're giving it serious consideration. if it's something you tried already, try to sound tentative when you say, "Would that be like the time we did this? because what happened then was such-and-such. Then there was the time we tried it again, and got X asa result. Can you see how we could have done it differently? Maybe there's something else we haven't thought of. What do you think?"
You have two possible outcomes from all this.
1) The school will feel vindicated, but will also begin to see that you have done more for this boy than they thought. But you may all begin to fele there is not much left tat you can do.
Or
2) The school may treat you a bit like an idiot, but at least they won't be so down on you. They're also more likely to feed you true information on things difficult child may be doing wrong at school, because they're sure as H not doing that now. And you NEED that info, so you won't get caught by surprise with what difficult child does next.
It's better for the school and staff to think you're idiots but well-meaning, than to think you're callous, cold, indifferent and that difficult child is a lovely kid who is abused. Think - Columbo. By seeming to be an idiot, he got a lot more information out of his witnesses than he ever would have if he showed them how smart he really was.
I've mentioned in other threads how to dress for a school interview - my suggestion is generally to dress like a Legal Aid solicitor (budget lawyer) - slightly expensive but dowdy. But in this case - you need to dress like the rest of the demographic. DON'T dress like professionals, dress like a housewife. If you go there from work, make a point of kicking off your work shoes, or changing down into something a bit more relaxed. Give them what they are familiar with, do your utmost to not intimidate them (speaking from experience, I know I can be very good at intimidating people, I have to sometimes work at NOT intimidating people). This is not a time, in your case, to look like "old money". Instead, go for the wage slave assembly-line worker look. Make it clear that you HAVE to go out to work to pay some nasty bills, and your boss is one thread away from firing you for all the time you are taking off to deal with the school. But of course, you will take that risk for difficult child because he is your husband's darling son. However, you need to keep your job in order to help pay the school fees. Or somesuch.
But grovel if you must. Bow to their superior wisdom. Ask teir advice. make it clear they are the education experts. Maybe if we all put our heads together, we can work as a team to help this boy and help everybody else. Home and school as a team, coordinated. Great communication.
That's why you tell the school that you've found $20 that can't be accounted for, then let them talk. Ask if they have had any go missing, if they don't talk. Ask if they can be certain that he did bring in the $120, or is sime kind staff member perhaps covering for him without realising? (don't ask that l;ast, uless you get absolutely nothing fomr them when you first mention it). Be kind to the school, someone there was trying to be kind to your son. They sound like lovely people - just stupid and very misguided. And enabling. But lovely, kind people.
Good luck. This needs to be Academy Aawrd material. After you've succeeded with this, go join a local theatre revue group, because you will have all that you require to make it as an actress!
Marg