Must I replace the value of the lost winter clothing package, worth 800 Riyals, which my husband did not receive and which was intended for workers, or is it permissible for me to pay it as an endowment (waqf) or zakat on behalf of the people who donated it, especially since the winter season has ended?

The wife is guaranteed clothing if there was negligence in receiving it, because an agent is liable if he is negligent. A similar item must be guaranteed if there is a similar one, or its value if there is no similar one. It is not permissible to pay its value in Zakat (definition), or in another expenditure like an endowment (waqf), except with the consent of its owners.