Two solutions in theory, to be sure. She does not have to apply both to solve the problem. I even know what the solutions are, in the vaguest possible terms: she has a cursed and evil magic item, which was once a beneficient one, but was stolen (because such evil doing adds to the evil magic), and turned from gold to lead, which means she can find a way either to turn it from lead into gold, or to reverse the earlier transformation. . . .
As soon as I figure out suitably dramatic ways for her to do both, I can decide which one she will actually use, and therefore, which one she will spend most of the book's length pursuing -- which is to say, is the other one. She switches at the climax. 0:) But first I have to figure it out. . . .
There are obviously not alchemists on the street corner in this universe. I'm not even sure there's a philosopher's stone.
Whether you build from the bottom up, starting with bright ideas and linking them up, or from the top down, getting overarching ideas and filling in the details, it's always fun to work out the issues.
Coming to think of it. this one started out with an overarching idea, ripped off The Lord of the Rings -- where we have the two plots of the need to destroy the nefarious magic item and the war with the Dark Lord going on simultaneously -- and sliced in half. What is it like to try to destroy the object that will bring destruction when you know it won't happen for a few centuries? Before it even promises any harm? Though now that she actually has to figure out how to destroy it, I'm not sure that she wouldn't tell Frodo that dropping a ring in a volcano was at least determinate.