Oh dear...
I've been sort of following you and your son in the last thread you made about his use of his stuffies. Is there any way you can, I dunno, lodge a formal complaint against this therapist? She obviously is much more than a "bossy lady" and the words I'd like to call her, I won't say. However, something must be done so she doesn't do this to another child.
I would just comfort him and reassure him that he won't ever lose his stuffies again. Hug him tightly like techgal said. Maybe allow him and his stuffies to do a special activity that he finds really enjoyable for a while.
I'm not a parent, but I do feel for you, as I have autistic tendencies myself, and am probably a very highly functioning autistic person or something.