Use two extension on the his phone. The first one to call his team member and configure the caller ID as Mr.Smith. and another extensions to call other users. One this second extensions configure the caller-id Mr. Smith Department.
When calling from second line to show the primary calling number do some translation . so that other users will still see his primary number and the name as Mr. Smith Department.
2.12.0.0
2.12.0.0