Unless his fixated goal is one of benevolence and general assisting of people, I will try find some other way of doing it. As my initial story arc, I believe after going wow, she will set her mind to the assistance of all in Amestris. Maybe give them a really flashy new city made out of unflawed Obsidian.

Alternate suggestion to the divine shard is to leave it vague and just have whoever is interested in it come down and say 'hey, that's my shard' and then plot.

[@Cyclone]