Haw. Rev. Stat. § 531B-11: Immunity.

No funeral establishment, cemetery, mortuary, crematory, or hydrolysis facility or any of its officers, directors, members, partners, funeral directors, managers, or employees who reasonably rely in good faith upon the instructions of an individual claiming the right of disposition shall be subject to criminal or civil liability or administrative or disciplinary action for carrying out the disposition of the remains in accordance with the instructions.