I'm not sure I've completely nailed this one, but I've spent far too much time on it, and I'm well into the "diminishing returns" phase of information gathering, so let's have a go.
Firstly the people:
Man 1 was a singer who rejoiced in the stage name of Dick "Hot-Cha" Gardner (real name Richard B. Baumgardner). He was a regular broadcaster, but took over the running of his family's restaurant after WW2. His name is perpetuated in the Richard B. Baumgardner Center for the Performing Arts in Clearwater, Florida.
Man 2 is Fran Frey, alto saxophonist and vocalist with George Olsen's Orchestra.
Man 3 is George Olsen, popular bandleader in the 1920s and 30s.
Man 4 is Gus Van (real name August von Glahn), who was one half of a Vaudeville vocal duo called Van and Schenck. He carried on as a solo performer on stage, screen and radio after Joe Schenck died in 1930.
Man 5 is George Hicks, an announcer for NBC radio. He is probably best known for a recorded news broadcast he made from USS Ancon, giving an eyewitness account of the D-Day landings in Normandy in 1944.
And the lady is Ethel Shutta, singer with the George Olsen Orchestra. She became more popular than Fran Frey (especially with Olsen, who married her), and she became the main vocalist, while Frey went back to his saxophone.
So what links them? They were all broadcasting for NBC radio in the early 1930s. I thought that the link might be the Jack Benny Show, but I can't find any mention of Gus Van ever being on that show, though all the others were. However, the Associated Press radio column of 22 December 1932 mentions a forthcoming radio show, though I haven't found exactly what it was called. It says:
George Olsen’s orchestra is to begin a new week-end series on WEAF-NBC the first Saturday night in January [that would be 1933]. Gus Van will “run” the show and there will be Ethel Shutta, Fran Frey and “Hot-Cha” Gardner as soloists.
This doesn't specifically mention George Hicks, but as he was a regular announcer on NBC, maybe he was involved as well, but that's as far as I could get.
The car? Well, there's a photograph of all six with an Oldsmobile L-series eight-cylinder convertible coupe, circa 1933. Again, I'm not sure why. I'd guess it's a publicity shot of some sort, but whether it's for Oldsmobile, their radio show, or whatever, I haven't been able to find out.
Anyway, pictures below, as requested.