If the war ended after a Union victory at Bull Run and a march on Richmond in late 1861 (unlikely, but not impossible), then at best, the resolution would be an amendment saying that slavery is banned in the territories, but was guaranteed in the states which already had it. That would eventually lead to a slave revolt.
This is why the status quo was impossible and war was inevitable. As the slave populations increased, the threat of slave revolt increased. The higher the concentration, the more restrictive the state governments became on free speech, religion, anything that threatened to potentially cause a slave revolt was brutally suppressed.
Furthermore, spreading slavery was a matter of life and death, of survival as much as it was about profits and politics. Spreading out the concentration of slavery reduced the risk or servile insurrection as they called it. So the growing population of slaves correlates with the increasing intensity and determination behind the fire eaters and similar minded politicians. Over time this frantic attitude, this sense of desperation for more territory, would lead to the corruption of the courts, of state's rights (Fugitive Slave law) and of the Democratic Party, the only vehicle left for them to exercise political power.
I don't see this emphasized enough as a leading motivator behind the temperature rising among Southern politicians leading up to the civil war. That is why Lincoln's "moderate" plank of restricting slavery to where it already was, was regarded in the South as basically a death sentence. whereas elsewhere it was seen as reasonable, even to many a racist working class type who didn't want the competition for jobs (people who had voted Democratic on the basis that slavery could effect the same end of preventing such competition, The South themselves destroyed that narrative).
