Is charity with the intention of transforming something deemed evil into good, after multiple Istikharahs, supporting visions, and failed attempts to turn away, accepted and made good?

If something becomes unattainable for you, and its acquisition becomes impossible, then you must turn away from it and know that what Allah has decreed is good. This is the meaning of Istikhara. However, if there is still a way to acquire it, and your soul yearns for it, then there is no harm in repeating the Istikhara and proceeding to take the means to acquire it. There is also no harm in giving charity with the intention of facilitating its attainment. But when its acquisition becomes impossible, then you must submit to Allah's judgment and be content with His decree.