That is quite a narrative. Here is what the text from Romans 11 actually says:
"17 And if some of the branches be broken off, and thou, being a wild olive tree, wert graffed in among them, and with them partakest of the root and fatness of the olive tree; 18 Boast not against the branches. But if thou boast, thou bearest not the root, but the root thee. 19 Thou wilt say then, The branches were broken off, that I might be graffed in. 20 Well; because of unbelief they were broken off, and thou standest by faith. Be not highminded, but fear: 21 For if God spared not the natural branches, take heed lest he also spare not thee. 22 Behold therefore the goodness and severity of God: on them which fell, severity; but toward thee, goodness, if thou continue in his goodness: otherwise thou also shalt be cut off. 23 And they also, if they abide not still in unbelief, shall be graffed in: for God is able to graff them in again. 24 For if thou wert cut out of the olive tree which is wild by nature, and wert graffed contrary to nature into a good olive tree: how much more shall these, which be the natural branches, be graffed into their own olive tree? 25 For I would not, brethren, that ye should be ignorant of this mystery, lest ye should be wise in your own conceits; that blindness in part is happened to Israel, until the fulness of the Gentiles be come in. 26 And so all Israel shall be saved: as it is written, There shall come out of Sion the Deliverer, and shall turn away ungodliness from Jacob: 27 For this is my covenant unto them, when I shall take away their sins."
The Deliverer out of Sion has already come. Correct? In the future, "he will come again to judge the living and the dead." He has been and still is turning away ungodliness from Jacob and will continue to do so until the End. The text of Revelations is even less clearly related to your narrative.
Such a dispensationalist narrative was proposed for the very first time during the Nineteenth Century by the Irish preacher, John Darby. Later, the Darbyist narrative was widely popularized by the massively promoted Scofield Reference Bible. Look up Scofield Reference Bible on the Internet. You will be amazed. There is no historical record of dispensationalism existing before the Nineteenth Century.
Nope...Jesus came the first time but He did not deliver anyone from anything...When He comes again, He will deliver Israel...
Rom 11:8 (According as it is written, God hath given them the spirit of slumber, eyes that they should not see, and ears that they should not hear;) unto this day.
He has been and still is turning away ungodliness from Jacob and will continue to do so until the End.
Nope...
Rom 11:13 For I speak to you Gentiles, inasmuch as I am the apostle of the Gentiles, I magnify mine office:
Rom 11:26 And so all Israel shall be saved: as it is written, There shall come out of Sion the Deliverer, and shall turn away ungodliness from Jacob:
Rom 11:27 For this is my covenant unto them, when I shall take away their sins.
This prophecy is about Jews, not Christians and it is future, not present...They is not you, and you is not them...
Such a dispensationalist narrative was proposed for the very first time during the Nineteenth Century by the Irish preacher, John Darby.
Clearly, that's not accurate...That dispensationalist narrative was first given by the Apostle Paul...
The fact that Rome did not and still does not acknowledge the fact is of no consequence...Well actually, it is...And it's very bad consequence...