Machito seems to be the accepted leader of the band on those tapes by now.
This was not always the case. In the liner notes to the 1979 Spotlite reissue 'Afro_Cubop', Mark Gardner writes about these sides:
'Which brings us to the three titles by an unknown Afro-Cuban Orchestra recorded in New York around May 1950.There are many ifs and buts about these performances. Was is Machito (unlikely) or perhaps Tito Puente? They were supposedly recorded by the late jazz historian Marshall Stearns and it is believed that Frank Socolow was a member of the reed section. Scanty data, to be sure, but of one fact we can be certain: Charlie Parker is the alto saxophonist on Mambo and Lament for the Conga. He may also be present, without soloing, on the dance number Reminiscing at Twilight.