Ezekiel 34 suggests that God, after the age of the completion of the visitation of the father's iniquities upon their children during the third and the fourth age of the existence of Isael, will once more begin to gather the Israelites to Himself. He will plant them in His fertile soil/field and teach them on the religion of Israel based upon the foundational truth that will come down out of heaven as a rock during the time of those kings.
I would suggest to you that the "ever again" is the translators understanding and not God's understanding as expressed elsewhere in the scriptures. In Jer 31:31ff God stated that He would make like new again the covenant that He had made with them at Mt Sinai to become a Kingdom of Priests, a Holy Nation and His Possession among the Nations Covenant.
This suggests to me that they will in our near future begin to produce fruit once more after God gathers them to Himself.
This verse is off the topic of the question that Israel was rejected by Christ for all time after that.
This is indeed Christ words but we should also read a little further where He went on to say: -
Luke 20:17-18: - 17 Then He looked at them and said, "What then is this that is written:
'The stone which the builders rejected
Has become the chief cornerstone'?
18 Whoever falls on that stone will be broken; but on whomever it falls, it will grind him to powder."
NKJV
Matt 21:43 repeats what Luke 20:18 states.
I am not sure that the verses you referenced actual supports your claim that Israel has been done away with by God forever.
Shalom