The executives were reluctant to launch such a risky venture.
Literal
Executives [topic-は] such dangerous enterprise [to-に] embark-[nom-の][obj-を] were-hesitant.
しぶる ('be reluctant, hesitate') takes the hesitated-about action as a direct object, often with の nominalization: する-のをしぶる, 行くのをしぶる. 乗り出す ('embark on, step out into') combines the compound verb pattern 乗る+出す, and is especially common for starting new ventures, undertakings, and risky projects.