If I vowed to give money in charity should I repeat an act that I thought was forbidden, then it became clear that it is a matter of jurisprudential disagreement between prohibition, detestability, and permissibility, do I have to give charity when repeating the act, taking the opinion of those who permit it?

The statement made by someone, "If I do such and such, I will give so much in charity," is considered a vow of contention (nadhr lajaj). What is obligatory in this case is one of two things: fulfilling what he committed to, or offering an expiation for it like the expiation for an oath, due to the Prophet's (peace and blessings of Allah be upon him) saying: "The expiation for a vow is the expiation for an oath." The expiation for an oath is feeding ten poor persons, or clothing them, or freeing a slave. If one cannot find [any of these], then it is fasting for three days.