My first thought is that your SpEd Director has convenience for him/herself in mind rather than the students. That mix of disabilities is a recipe for disaster, especially putting the BD and Autism students together.
Anyways, my helpful thought is to use WBT but at a low volume on the volume-o-meter. Have everyone excitedly whisper their Oh Yeahs! It can be just as fast-paced and excited, but just not as loud.
Honestly, if your student is supposed to have a unique space with no distractions, then a class with BD students is not it, and at that point your director is violating the law. You're in a tough spot. I would just bring it to your director's attention that he/she is putting the district at risk of litigation with that student in that environment, and write that down somewhere so if it does come to that you have a record.
WBT Intern 2011-2012