I would have the student come to my office. I wouldn't, however, invite another prof or have a tape recorder. I think that's a bit overdone for the crime of chattering.
Maybe, but I've used the tape recorder based more on a "gut" feeling about a particular student more than the actual crime. Some students know how to play the system and don't care what happens to the people they play with.
It's up to the OP to decide whether or not her student is one of the destructive ones.