jocelyn,
first of all, welcome to sober recovery. i hope you will continue to come here, to glean insights from others, and to process the enormous stuff you are dealing with.
i think that if he's going to get, and stay, sober, he certainly can do it inside or outside your home. as learn andlexie have said, let's try and turn this a bit and make the discussion not about what's best for him, but what's best for you. your children, yes. but what is best for you is assuredly what is best for them as well.
i understand that you don't want them to leave their beloved school, or for you to have to move and such. but that's just your fear talking. please don't stay stuck in a situation of this level of dysfunction so that they won't have to experience changes like that. those things are things. your sanity, your calm and content disposition, are infinitely more important. really. i believe this with all my heart.
my children were older when i broke up our family. but you know what? when my oldest daughter was 19 or 20, she wrote on facebook for all the world to see, that she wanted to be like her mother when she grows up, because her mom is "so smart, and strong and i love her so much"
it's the best things anyone has ever said to me. and i think i remember it because when i think of her saying that, it's all about how i had the courage to do what i believed i needed to do.
it takes courage, and discernment. you're still working through that second one. you'll get there.