[The Prohibition of Handing a Vowed Offering to a Custodian Who Will Consume It]

Answer – and Allah is the One who grants success: Handing it over in such a situation is not permissible and does not suffice; rather, it is obligatory upon the one who made the vow, or the one who established the endowment, to safeguard it until he is able to place it in its proper place.
The proof of that is the generality of His saying the Exalted: “Indeed, Allah commands you to render trusts to whom they are due.” [al-Nisāʾ:58]

Source: Min Thimār al-ʿIlm wa al-Ḥikmah vol.2