Hello Saul,
I do not think the “Suite Concertante” by Moreno Buendia was commisioned by Gretchen Van Hoesen. “Suite Concertante” was written in 1958 and it was awarded “Premio Nacional de Musica” in Spain the same year. The first performance was by Marisa Robles with the RTVE orquestra in 1974, subsequent Robles recordered with the London Philharmonic Orchestra. Ms. Van Hoesen gave the first performance of the piece in the US… I agree with you,