"Butchered" definitely implies she killed them. Especially since Maya differentiates between that and maimed, tortured, etc. Implying there's a notable difference.
Psycho Ami also apparently anal raped them, unless Maya meant something else by "Sodomized", so, damn.
Then again, we can't really take Maya's words as fact. She's been wrong before, and both Maya and Tsuneyo have acknowledged that Maya's memories may not even be accurate. Or as Sensei said:
she might just be "programmed" to think what she does.
Or As Tsuneyo noted:
Maya may not even be meant to be trusted.