The two are less than thirty years apart, so it’s not impossible; and since the latter is set in the ‘20s, and they hired Barbette as the drag consultant, I’d escalate the chances to “pretty likely.”

I agree it's not impossible. It's just a <30-year span in which movies and actors from the pre-Code era can be documented to have vanished, and I'm not sure literally when some of the people involved in Some Like It Hot could have seen Peach-O-Reno if they missed it in theaters—Wilder didn't emigrate to the U.S. until 1933. It just feels metaphysically like someone should've.