I think you misread Lincoln intent in supporting a 13th Amendment- The Corwin Amendment.
He did it to avert war, but also to encourage further debate on the issue as well.
The southern states decided that if they created a new country where slavery was legal, They didn’t have to pass the 13th amendment at all
By 1861, the country was riven and the conversation was about over. The Southern States were collecting their hats and coats and calling for their carriages.
The 1859 John Brown raid, while Lincoln did not endorse it or bemoan Brown's capture and execution (very conspicuous, leading "others" -- including almost the entire New England intellectual establishment -- did, publicly and for the record) had destroyed the last remnants of civil union and fellow-citizenship (as per T.R. Fehrenbach and other historians I've cited in the past). When some people tell other people, "we wish you were in fact dead in the ashes of your houses; you deserve it," the community is finished.
lincoln was a stone RACIST & couldn't have cared LESS about slavery or "freeing the slaves", EVER.
ALL he was interested in was more POWER for himself & more MONEY his "merry band of thugs, war criminals, freebooters, BIGOTS, etc." that composed the "high command" of the unionist MAL-administration.
free dixie,sw