Does the failure of a patient to recover after giving charity with the intention of their recovery mean that Allah has not accepted the charity, even if the charity was from the heart and from precious wealth?

Healing is in God's hands. Giving charity on behalf of the sick is prescribed as a form of intercession through good deeds. It has been reported in the hadith: "Cure your sick with charity" — even though there is some discussion about its authenticity. It repels diseases and ailments. The charity might be accepted, yet the healing is delayed due to divine wisdom, or it might avert another calamity, or it might be stored for the afterlife. In any case, the one who gives charity is rewarded.