Kidnapping plot issue that I've not considered

[L Verge]

Speaking of kidnapping plots: I may have had my head stuck in the sand for all these years (no comments, please), and Bill Richter may have covered this in Last Confederate Heroes, but I swear I just read this for the first time today while reading "A Vast and Fiendish Plot" by Clint Johnson regarding the 1864 New York fires:

--The operatives attempted one last operation in December of 1864. They planned to kidnap Vice President-elect Andrew Johnson on his way to Washington for the inaugural. Events prevented them from taking him in his hotel room in Louisville, Kentucky and their second attempt also met with failure. When they rushed into the vice presidential suite they found it empty. Johnson left earlier after deciding to continue the journey by boat instead of train.

This was part of the Northwest Conspiracy being hatched in Toronto. I did further googling on this because one of the operatives in that conspiracy was the Confederate agent, Thomas Hines of Kentucky. My grandmother's maiden name was Hines, and she hailed from the area where Virginia, Kentucky, and North Carolina are so close. She also married a Mays, and there is a town in Kentucky named Maysville. Genealogy confuses me terribly, so I have never really pursued the line.

Anyhow, does anyone have further details on the Johnson kidnap plot?