I would ask them how many chances they had given your DS to be in educational environments suited to his ability level.
I would also suggest that "more structure" is likely to exacerbate any perceived issues with authority.
I would ask to see detailed complaints so I can understand exactly what we're talking about. Not interested in general, unsubstantiated teacher whining... I want documentation for each time he was sent to the dean's office that describes each incident in detail and what the plan was to resolve each issue.
I would also suggest that a segregated, small program is exactly the kind of educational environment that research supports for children like yours, but it should be defined by ability level, not disciplinary level.
