Bringing back a dead hamster which fate clearly decided should not be alive would really be dancing with the dangers of chaos theory. You try and dissuade her using the butterfly effect.
“Sarah, have you thought of the potential consequences of bringing back a dead hamster using such experimental means?”
“I mean yes, the obvious consequence of I get my Dini back!” she answers.
“No I mean, doing something so out of the natural order could invite in some chaos sprouting forth a dangerous consequences for the world like…he could bring forth a dangerous mutation from the Banach Tarski transformation that spreads to other hamsters killing them all, or even spread to humans! You could be messing with the biological order of the earth doing this. Even spiritually, what would be the ramifications if we found out that we never had to die? It could be a deadly butterfly effect!
“Well, this was an unnatural death, I’m just undoing the butterfly effect of Sir Meowsalot ending a life before his time is up. You know I don’t buy into all that alternate reality mumbo jumbo, that’s just something the Marvel Universe uses to make more superhero movies!” she paused for a breath. “…and for the deadly disease, we’ll quarantine him here just so we know he’s safe.”
“Yeah, but we named him Dini for a reason, he’s always escaping—”
“That’s why I got extra rolls of duct tape to keep him inside his hamster cage for once, aaaand I’m putting a metal cage around his tube fortress for added protection.”
She’s still unphased by your reason, and laughs in the face of uncertainty, what do you do?
Use the ship of Theseus argument, a Dini copy wouldn’t be the same hamster when you think about it.