Not true. She automatically excommunicated herself when she set herself up in Holy Orders.
The same way people hurt themselves when they jump off bridges: just as certain, just as automatic.
She abused a Sacrament; she knew it; the excommunication could have ben lifted by confession, if the Pope so authorized. Only God knows whether in hr final moments she repented; so all we can do is pray for her soul, poor woman.
In my opinion (and only my opinion, dearies) every single Bishop who refuses to carry out Canon 915, should be excommunicated for sacrilege against the Eucharist. That's the Canon that says unrepentant people guilty of manifest grave sin (e.g. Catholic politicians voting for abortion or target=city bombing or gay marriage or torture or the like) MUST (the law says "must") be denied Holy Communion.
But the bishops themselves are openly disobedient.