We have very different beliefs, Jews and Christians about forgivenss.
In Christianity we are told to forgive and Christ even modeled forgiveness of his own executioners from the cross. But forgivenss does not mean no punishment. No retribution. Forgivenss has never meant that the deed is erased, just that our God values all humans and finds them worthy of redemption. Redeption and forgivenss do not preclude punishment.
Christ never said anything about forgiving the unrepentant murderer. Ever.
Read Luke 17 3-4.
Christians are told to forgive the truly repentant who ask forgiveness. None of the monsters who trained and sent these monsters has repented, and none has asked for forgiveness.
Therefore forgiving them is a decidedly un-Christian thing to do.
L