Ds2 had SEN, I homeeducated him when he was ,12 till 14. He has excellent GCSEs, fantastic a grade a levels, now at vg uni.
We never spent more than two hours max at table when home educating. I took him out a lot. He had no attention span, v impatient and anxious.
What he needed was to spend time outside doing practical things, sensory feedback, walking, travelling, socialising in small groups. Home Ed saved him.
Then he went back to school, all went v well.
He wasn't Behind, he was ahead cos his ability to learn and concentrate was so much greater. Hence good academic outcomes, but even if he had wanted to do something non academic and had confidence I would have said he was "ahead".
Home ed is about the whole person, maybe your dh has hit on something by talking about him going outside, doing his own thing etc..
It seems that you could discuss with your DH what your goals are, both parents, in home educating, read some points of view, ie detoxing, Sensory diets, how kids learn etc.
Structure is good, but it could be structure to have more unstructured time ifyswim. You also need to look after yourself, is your husband hitting a raw nerve by demanding you do housework, it is clear you are drained by the level of input required for your son, hence the anxiety.
So I am so sympathetic, you are doing a fantastic job and it isn't easy but there is a complex series of decisions at play here, and I think it begins with communicating with your husband, AND acquainting yourself with another pathway which might mean loosening up the way the day goes, leaving more time for YOU (not necessarily housework)