Politeness of the letter notwithstanding,
this was a premature bid on her end.
I agree that not everyone deserves to be chased around by their past actions, one look at Twitter can tell you why that's stupid thanks to cancel culture. However, animal abusers of that caliber are rarely not psychopaths. Even if she waited to request the takedown, I somehow doubt she'd ever get past that edgy bullshit her brain is wired to respond to.
They say that torturing animals as teens/young adults is a very clear sign of a potential killer. If anything, keeping it online will prove useful for prosecutors of the future when she eventually and inevitably murders a troon or something with her bare hands.