Steadfast Sentinel

The token copies exactly what was printed on the original card and nothing else, except the characteristics specifically modified by eternalize. It doesn't copy any information about the object the card was before it was put into your graveyard.

If a creature card with eternalize is put into your graveyard during your main phase, you'll have priority immediately afterward. You can activate its eternalize ability before any player can try to exile it, such as with Crook of Condemnation, if it's legal for you to do so.

Once you've activated an eternalize ability, the card is immediately exiled. Opponents can't try to stop the ability by exiling the card with an effect such as that of Crook of Condemnation.