Assuming the Russians at least try to follow the Geneva Convention here, they were going to be taken to a POW camp and stayed there until the war is over.

The conditions in such camp are likely to be awful (even for POW camp standards), but assuming the offer was genuine, the captain has acted appropriately enough within what was in his power, and doesn't seem to have gotten out of his way to make it worse than it always going to be, which is what the comment I replied to was about. Same can't be said about other Russian commanders.

If the Russians instead executed the surrendering Ukrainians (or tortured them or did some other atrocities), that would have been a war crime according to the Geneva Convetion. Was the offer genuine? We'll never know.

Regardless of that, I respect the Ukrainians' decision not to surrender, it takes massive balls to stand face to face with death and tell your killer to go fuck himself, knowing damn well that takes away your last hope of making it out alive.