Puzzling: who was the conductor?

On 30 June 1969, Jorge Bolet gave a performance at Bloomington, Indiana, where he had just started teaching.

He played Rachmaninoff, Piano Concerto No. 3 in D Minor, Op. 30. Ralph Vaughan William's glorious Symphony No. 5 in D major was the other item on the programme.

On the Palexa CD that came out, Charles Webb is assumed to be the conductor. Several discographies list him as being on the podium.

However, The Indianapolis Star (25.6.1969) mentions that the conductor will be Wolfgang Vacano, and the review by The Herald-Times critic Zola P. Levitt (1.7.1969) lists him as the conductor of the evening, with "one of the largest audiences ever assembled in the IU Auditorium". 

Wolfgang Vacano (1906, Köln/Cologne -1985): in 1939, he had gone to South America and worked as a conductor at the opera houses of Santiago, Montevideo, La Plata, and finally at the Teatro Colón in Buenos Aires. From 1951 until his retirement in 1977, Vacano was a professor at Indiana University Bloomington, where he taught conducting and led opera workshops.