"The Friendly Man" that Scott Carrier worked for was, in fact, Charles Osgood. The daily radio show in question was "The Osgood File."
Here is the proof: Carrier mentions in the "This American Life" piece that "The Friendly Man" employed an executive producer for his daily radio segments who was based in San Francisco. Carrier also mentions that the segments reached an audience of 12 million. So, I introduce you to a San Francisco-based radio producer named Cynthia Perry. Here is a passage from a website called
carnegie.org that talks about Perry and Charles Osgood:
Her [Cynthia Perry] biggest success was her relationship with
the highly respected newsman Charles Osgood
of CBS Television’s Sunday Morning and CBS
Radio’s The Osgood File. She began a professional
relationship with Osgood in 1995 that, by the
time we met, involved producing one segment a
day, five days a week for The Osgood File, or fully
twenty-five percent of the segments each week.
Osgood’s radio feature airs on most CBS News
radio stations and at the time of the grant could
boast of an audience of around 12 million listeners
per week.