If it were recorded properly, I doubt Dixon would have been submerged. His tone definitely cuts through, even if it is dusky. But given the actual history of the time I cannot really imagine him being on that record. Steve Lacy would've been fun, but he was in Europe at that time.
I also don't think of Allen and Dixon as among the younger 60s crop; they were born in 1924 and 1925, respectively.