I like it. It does make it richer. Very cool.
OTOH, I agree with Wendy that it might be nice to mention damage to the timestream, too. Paradoxes resulting from the fact that she went back to that point because she'd seen the bones from later. The injunction against fixing your own mistakes. Something along those lines.
But then, adding in other concerns takes away from the focus on raising the dead, which is a pretty big deal. Huge temptation to a time traveller, and something generally considered to be Very Evil.
Also, obviously, different ideas/reasons work better for different people. We all have our own perspctives, and since it's your story, yours is the ones that counts most.
So... I don't know. It works quite well as it is. Might work a bit better if you threw in a nod to the other issues. An extra sentence or so between these two:
"An act that was so unethical as to be nearly unspeakable. Unthinkable."
OTOH, that does kind of lessen the impact her dilemma, doesn't it? Save Utopia by breaking one of the most fundamental ethical rules of her job, or let it all come apart when one deceptively simple action could solve everything? That is a very neat little insert, and adding in paradoxes and other rules would only confuse the issue and make the choice a little too easy.
Okay, then. What you have didn't immediately strike me as the best way to go, but, upon reflection, I'm thinking that it is. Sorry to give up one of my pet ideas (Go, little idea! Go run! Go play! You're free! <sniffle>), but I think what you've got is actually better. I was coming at it from a technical angle, but what you have is something that solves the issue while adding character depth. Go you!
Paul
