I have been listening to a few Andy Secrest solos with Bing Crosby in 1937:
From July 17, 1937: "Smarty" https://www.youtube.com/watch?v=-jWU236_EOU
From September 20, 1937: "Remember Me?" https://www.youtube.com/watch?v=t5gq_nso9V0
From September 25, 1937 (with Connie Boswell in duet with Crosby):
"Basin Street Blues" https://www.youtube.com/watch?v=mhea3oL9JQs
"Bob White" https://www.youtube.com/watch?v=vQUagfWetZM
What these show pretty conclusively to me is that by 1937 Secrest was his own man, a far cry from the Bix soundalike of the Whiteman years. Yes, there is still some Bix (and perhaps Red Nichhols) influence in some of them, but nowhere does Secrest sound like a mere imitator, and in Basin Street Blues, there is little Bix influence--if anything it is closer to Armstrong.
Unfortunately, Secrest's reputation as a Bix imitator is probably unalterable--but, especially if one looks at his post-Whiteman career, it is unfair to a player of considerable talent.
No hint of Bix.
https://www.youtube.com/watch?v=NAbcyC5 ... e=youtu.be
Andy Secrest (tp) Irving Verret (tb) Eddie Miller (ts) Marvin Ash (p) Nappy Lamare (g) Country Washburne (b) Zutty Singleton (d)
Los Angeles, November 15, 1949