Because of your initial wording "unrelated to RCA Custom", I got the impression you didn't want me to assign this to RCA Custom. After your clarification, I guess I can leave it as a RCA Victor Custom release.
Again, RCA rented or leased studio space from Radio Recorders in this time period, up to 1959. This is why, on this particular RCA Custom pressing, Radio Recorders master numbers are in evidence rather than RCA's own. This would have been sometime between 1949 and 1953. Don't know when RCA's own numbers (which, as of 1953, would have been RR-E3-CB-#### on recordings from there) took effect for jobs from Hollywood.
Meanwhile, this appears to be an RCA Hollywood pressing, with Bert-Co label fonts.
So what would you call this label? Radio Recorder may have made the original recordings, but the label says "Pressed by RCA Victor Division of the Radio Corporation of America." As an RCA Victor pressing, shouldn't it be listed under some kind of Victor heading?
M. W. Sherman, in his "Collector's Guide to Victor Records," 2nd ed., p. 235, discusses such recordings under the heading Contract Pressings: Institutional. He dates the Batwing label style of these records to late 1930s - early 1940s. On page 237, he claims that this label was replaced with a banner label that said RCA: A Custom-Made Record," starting in July 1944. On the same page, however, he shows custom-made records from the early 1950s, such as one made for the NAACP, that still have the Batwing style label.
The 'RR' numbers indicate recording at Radio Recorders on Santa Monica Blvd. in Hollywood. RCA rented or leased recording space there for several years until early 1959. In fact, RR-16934/7 were Radio Recorders masters and unrelated to RCA Custom.