I am having trouble understanding the wisdom of having what sounds like three aircraft (two helicopters and a Cherokee) vectored to search for the Bonanza. I kept wondering if the controller was thinking to himself "what have I done? I'm about to cause a secondary mid-air". The controller watched the Bonanza descend at an apparently controlled rate. Why not simply call local emergency crews to the scene rather than vectoring aircraft together whose pilots have probably not been trained to fly search patterns? Am I being overly cautious?
Yes. The aircraft searching were all under his control. The planes that had the mid air were not. The local services were called but having aircraft from above search for the accident aircraft can locate where exactly they are in order to get to the occupants faster. Almost every time there is an event like this multiple pilots volunteer to help.