In 1970, Wright Esser (11 episodes), Nelson D. Fair (9 episodes), and John C. Hurd (1 episode) formed the Hawai‘i State Theatre Council to provide “a representative body to encourage, promulgate, and propagate theatre arts.”
The founding officers and directors included six Hawaii Five-0 veterans: John C. Hurd, Newell Tarrant (5 episodes), Nelson D. Fair, Electra Fair (Gailas, 7 episodes), William Croarkin (2 episodes), and Lee Stetson (8 episodes).
Jack's name was not mentioned, but what do you bet he was active on the sidelines, perhaps as an advisor?
Source: The Hawai'i State Theatre Council. http://hittingthestage.com/theatre-council/