Is it permissible to seek healing through slaughtering purely for the sake of Allah to treat sorcery (sihr), the evil eye (ayn), and jinn possession (mass), based on the hadith "Cure your sick with charity" and the Prophet's (peace be upon him) saying "There is no harm in ruqyah as long as it does not involve sin or shirk"?

The correct part of the hadith is: "Cure your sick with charity," and Al-Albani graded it as hasan (good). As for the addition "and purify your wealth with zakat," it is fabricated (mawdu‘), and the addition "and meet the waves of بلاء (affliction) with du'a (supplication)" is weak. It is permissible for a sick person to give charity by slaughtering an animal, hoping for recovery, as charity is a means of healing. Charity is not limited to slaughtering, but also includes food, clothes, and money. The mentioned supplication has not been reported in the Sunnah, so one should not restrict oneself to it. It is legislated for a believer to supplicate to Allah to accept their righteous deeds.