Teddy Wilson June 1, 1937
Per the Festival Handbook, by Schapp and Young, the main bass player appears to be Artie Bernstein, with Walter Page subbing on one track. The authors present a photocopy of the Brunswick/Decca recording session log stating this, plus stylistic evidence based on their knowledge of differences in Berstein & Page's style.
In addition, we follow most sources in stating that this is a Teddy Wilson session, especially given Holiday's absence on one track. Lubbers calls it "Billie Holiday with the Teddy Wilson Orchestra," presumably because he is interested chiefly in Holiday. Lubbers and Varela do not present the instrumental track, again for this apparent motivation to document only Holiday.