Eustache performed on 21 solo woodwind instruments under the baton of his fellow-countryman Gustavo Dudamel with his "Orquesta Sinfónica Simón Bolívar" in Caracas, Venezuela.

He has done studio sessions for movies as a flute/woodwinds instrumentalist, including being the main world woodwinds soloist for Mel Gibson's The Passion of the Christ soundtrack, written by John Debney.

[citation needed] He played Middle-Eastern flutes, reeds, and Armenian duduk featured in Steven Spielberg's Munich (nominated for both the 2006 Oscars and the 49th Grammy Awards for "Best Soundtrack"), composed and conducted by John Williams, as well as King Kenacho & Bs.

[8][9] Eustache's world flutes and woodwinds solos are featured on Paul McCartney's songs "Jenny Wren", and "Growing Up Falling Down" which appears on the single Fine Line.

Eustache was a featured performer of South American woodwinds and Afro-Venezuelan percussion on Gustavo Dudamel's "Libertador" orchestral suite, with the Los Angeles Philharmonic at the Hollywood Bowl in the "Noche de Cine" concert special, July 30, 2014.

He was also a house band member for Edward James Olmos' Americanos Concert with Latin Superstars Cachao Lopez, Gloria Estefan, Paquito D'Rivera, José Feliciano, Juan Luis Guerra, Sheila E., held at the Kennedy Center, Washington D.C., for the PBS Presents series.

With the ORF Radio Symphony Orchestra, he played flute and cuatro at the Hollywood in Vienna 2018 dedicated to Hans Zimmer score film music.

His enthusiastic performance and seamless transitions between several wind instruments were immediately noted by viewers, most notably during the Xenoblade Chronicles 3 section of the Orchestra's medley, who kept the hashtag #FluteGuy trending on Twitter throughout the night and were regarded by many as the highlight of the entire awards show.