Thank for bringing that (Father, forgive them) to our remembrance.
It take the supernatural power of the LORD to pray like that and to forgive like that.
In the garden of Gethsemane (Mk 14:36), if Jesus had not added the words, "nevertheless not what I will, but what thou wilt",
would the Father have answered his prayer, "Abba, Father, all things are possible unto thee; take away this cup from me"?
So, when (Lk 23:34) Jesus prayed, "Father, forgive them; for they know not what they do", did the Father answer his dear Son's prayer?
If he did answer his prayer, then those people crucifying Jesus, were to be forgiven that.
Unless I'm confused, the only way to be forgiven, when we're guilty of the blood of Jesus, is to be saved and washed by that very blood.
That would indicate to me, that everyone at the cross, sometime before they died, had the opportunity to be saved.
Maybe for some, it was 40+ years later.
However, since one of the two thieves got saved, and the other apparently died, and went to hell,
the all those people at the cross, at some point, had the opportunity to believe the gospel, or reject it.
The Father answered his Son's prayer, while yet still allowing man a freewill to choose whether he wanted to be saved & forgiven, or not.