We discussed this in a previous topic at Conditional discharge recall and s117 responsibility and eventually came to the same conclusion as you about the meaning of the Supreme Court decision.
However, in the older case of R (Wiltshire Council) v Hertfordshire CC [2014] EWCA Civ 712 the Court of Appeal decided that a residence condition meant the place of residence was not voluntary and so the patient was not “resident” there. Maybe the “recall” local authority will argue that the Supreme Court’s comments in Worcestershire about voluntariness were just obiter, and that the “original” local authority again has responsibility.