Not all therapist are created equal and from the abundance of therapy styles out there not everyone fit for every person and every situation. Most parents in these boards have met more than one therapist who has read their and their child's situation totally wrong or has in other ways been a really bad fit. I think most of those of us, who have had a pleasure to work with more than few, have met totally unsuitable ones for us and our families.
If this therapist is unsuitable for your son and family is a different thing. Sometimes change in style can help things get forward. But if the therapist in the rehab worked very differently, and did get through with your son and their work together was successful, that would be a benchmark for fitting therapist for me especially after so little time in therapy (could be different after a year or two with limited progress.) If current therapist has a very different style that doesn't get as good rapport going on with your son and doesn't seem to produce similar success than last one, I would change to the therapist whose style is closer to the therapist with whom he did work well with.
