Foster was Cedric Foster, who joined Mutual as a commentator in 1940. He was best known for his personal in-depth ours of European countries in post-WW2 Europe. "Twice a Day" Hemingway for Folgers Coffee was a staple of my childhood and was I believe a regional on Lee broadcast (Don Lee was a part owner of Mutual before General Tore bought it).
C Engle may have Claire Engle (
https://en.wikipedia.org/wiki/Clair_Engle ) who was a Democrat and California's senator until his premature death from a brain tumor
Norma Young I do not personally remember but internet sources say she was the KHJ Home Economist beginning in the late thirties and hosted the Homemakers Club quiz program during the forties and fifties. It appears to have been a KHJ rather than Don Lee network feature. However, there is a 1939 phto of her working with Lee's early television experiment in 1939 that identifies her with the network
http://www.sfmuseum.org/hist5/donlee.html Her radio program initially began on Hearst's KEHE and then continued after the station was acquired by Earle C. Anthony and merged with KECA. As Harrison Holliway revamped KFI/KECA to NBC Red and Blue network criteria Young's program moved over to Lee's KHJ, another example of the frequent synergy between the two Los Angeles broadcasters. .
Virgil Pinkley was editor of the evening version of the Los Angeles Times (called the Mirror News after a merger with the Daily News) and was sponsored by SAS to promote their pioneering polar route to Europe. I believe he was local to Los Angeles. I don't recall his on-air political slant but both papers were very conservative and pro-Republican. Pinkley, a USC Trojan, headed the United Press in Europe in the thirties and forties and was a mentor of Walter Cronkite and friend of Dwight Eisenhower
https://semichorus.wordpress.com/2013/05/26/a-different-kind-of-war-hero/
F Lewis was of course conservative commentator Fulton Lewis Jr, who was with Mutual for over thirty years. He was from an influential Repubican family - Herbert Hoover attended his wedding to the daughter of a former RNC Chairman. Before getting into broadcast journalism he wrote a column for the Hearst papers. When he died in 1966 his son, Fulton Lewis III continued the radio program until 1979 on several hundred Mutual affiliates. Honored in his lifetime he has in recent decades been vilified as non-objective for his strident anti-communist views.
https://en.wikipedia.org/wiki/Fulton_Lewis
The Answer Man was a Mutual program initially known for answering any question sent in by return mail. It originated ith Mutual's New York station WOR.
Haven of Rest began on KFI in 1934 ( see here
http://www.singers.com/gospel/haven.html ) and grew into a M-F ad hoc network - whether this included the full Don Lee network at some point I don't know, but it is now called "Haven Today" and is still heard on over 600 religious stations across he country (
http://www.haventoday.org/brief-history.php ). Another radio ministry uses the Haven of Rest name but there is no connection.
KHJ in those days was a very differently programmed station than that of its current owners. It also had kids programs such as the Cisco Kid, audience quiz shows such as Tello Test and of course Jack Bailey's Queen for a Day.