But the secessionists didn't come into play until Lincoln was elected. Strong or weak, the outgoing president couldn't prevent the election and he wouldn't have been able to prevent the Southern reaction to Lincoln's election. Negotiations would not have prevented Southern secession when they had no interest in negotiations, and threats of force would only have caused them to meet that threat with force of their own. The only thing the could have prevented Southern secession in 1860 was a Democrat victory.
“the secessionists didn’t come into play until Lincoln was elected”
That is simply not true. The secession was planned in the 1850’s long before Lincoln. Read The Road to Disunion: Volume II: Secessionists Triumphant, 1854-1861.
https://www.amazon.com/Road-Disunion-Secessionists-Triumphant-1854-1861/dp/019537018X
Read about the Knights of the Golden Circle. Read about Jefferson Davis, Caleb Cushing and the many others involved in the secession.