That is incorrect. Lincoln himself stated in his inaugural that he believed ratification would be a sure thing - so much to the point that he urged the country to treat it as if it were already enrolled. He even believed he could obtain ratification from the seceded states. Most state legislatures in the north took up the measure very promptly. The Governor of New York publicly endorsed it and one of the two chambers in several of the states passed it. But the war threw it off the list of priorities with only the four states I mentioned approving of it.
What Lincoln really said"
"This country, with its institutions, belongs to the people who inhabit it. Whenever they shall grow weary of the existing Government, they can exercise their constitutional right of amending it or their revolutionary right to dismember or overthrow it. I can not be ignorant of the fact that many worthy and patriotic citizens are desirous of having the National Constitution amended. While I make no recommendation of amendments, I fully recognize the rightful authority of the people over the whole subject, to be exercised in either of the modes prescribed in the instrument itself; and I should, under existing circumstances, favor rather than oppose a fair opportunity being afforded the people to act upon it. I will venture to add that to me the convention mode seems preferable, in that it allows amendments to originate with the people themselves, instead of only permitting them to take or reject propositions originated by others, not especially chosen for the purpose, and which might not be precisely such as they would wish to either accept or refuse. I understand a proposed amendment to the Constitution — which amendment, however, I have not seen — has passed Congress, to the effect that the Federal Government shall never interfere with the domestic institutions of the States, including that of persons held to service. To avoid misconstruction of what I have said, I depart from my purpose not to speak of particular amendments so far as to say that, holding such a provision to now be implied constitutional law, I have no objection to its being made express and irrevocable."
I suppose much of your misrepresentation of Lincoln's position comes from the last sentence, because nothing else in his statement concerning constitutional amendments even remotely supports you contention. The phrase "holding such a provision to now be implied constitutional law, I have no objection to its being made express and irrevocable," can easily be recast as "If this amendment is ratified, I won't oppose it or try to undo it." It was a salve for the Southern Unionists; but the issue of secession was politically too far gone.